So many mods to choose from. What I looked for 6 months ago is not what I look for now. At first I wanted lots of extra places to search so I loaded a bunch of player home mods. I found I would visit once, loot the place and never go back. Places to loot don't contribute much, if anything, to the game and those got dumped.
Here is my list of a few of the more practical mods I use and consider "essential".
[spoiler:b774d2f5d6]Military Backpacks - New Vegas Edition Blackwolf SedPL - Increase your carry weight up to 95 pounds. Purchased from vendors.
http://www.newvegasnexus.com/downloads/file.php?id=36423
Goodsprings Filler - Opens boarded buildings and adds a handfull of small quests. Gain a little more experience and gear at the beginning.
http://www.newvegasnexus.com/downloads/file.php?id=35121
Cheat Terminal - I use it very rarely, but on those special occasions, like when the game glitches, it comes handy.
http://www.newvegasnexus.com/downloads/file.php?id=35358
Light Step ED-E - Keeps the floating robot from setting off mines and tripwires, which it never should touch anyway!
http://www.newvegasnexus.com/downloads/file.php?id=35526
Improved Companions - Simply makes more companions available to you, based on your Charisma.
http://www.newvegasnexus.com/downloads/file.php?id=36949
JNF Sniper Zooming - Allows you to zoom in and out with your weapon scopes.
http://www.newvegasnexus.com/downloads/file.php?id=37060
MrSlackPants-DecentPipboyLightNV - Gives the puny Pipboy light a wider radius.
http://www.newvegasnexus.com/downloads/file.php?id=36957
[/spoiler:b774d2f5d6]
Now here's a list that may not be essential, but I consider them highly desirable.
[spoiler:b774d2f5d6]Plausible Starting Outfit - Replaces the vault suit with NCR courier clothing. Ridiculous to start with a vault suit when you didn't come from a vault.
http://www.newvegasnexus.com/downloads/file.php?id=35445
Perky Snowglobes - Each of the 7 snowglobes you find, which are already in the game, adds +1 to one of your SPECIAL scores.
http://www.newvegasnexus.com/downloads/file.php?id=38610
Water Tower Mini-Vault V5 Special Edition - A simple player home in Goodsprings that is frequently overlooked on the Nexus. It's not one of those overstocked arsenal homes. It's just a small hideout near the start of the game with a great view of Vegas, especially at night!
http://www.newvegasnexus.com/downloads/file.php?id=36271
Nevada Skies - Weather Effects BETA and URWLified - Makes the sky much more attractive and realistic. Also adds weather to the game. The title says BETA, but it works beautifully. It's cool when it rains.
http://www.newvegasnexus.com/downloads/file.php?id=35998
I Got Spurs - If you like the song "I Got Spurs", this is for you. This mod is fairly new and adds a set of spurs to the game with a +1 luck bonus. They work with any set of clothing or armor.
http://www.newvegasnexus.com/downloads/file.php?id=43382
Benny's Lucky Lighter - Changes Benny's lighter, when you find it, to grant a +1 luck bonus. Luck comes in handy.
http://www.newvegasnexus.com/downloads/file.php?id=42147
Improved Casinos - Increases the amount you can gamble in the casinos. Also increases the thresholds for getting free gifts from them.
http://www.newvegasnexus.com/downloads/file.php?id=39358
Powered Power Armor - Makes powered armor a little more powerful with more features and moddable. Also adds a few unique armors to the game, including the classic T51b hardened power armor.
http://www.newvegasnexus.com/downloads/file.php?id=37983
Radio New Vegas - The Secret Stash - Greatly increases the selection of songs on Radio New Vegas.
http://www.newvegasnexus.com/downloads/file.php?id=37029
I generally detest gun mods, but there is one more mod that is very popular. It puts a unique Desert Eagle into the game that is very attractive, gold colored, with much engraving. However, IMO, the gun itself is pretty weak.
44 Desert Eagle VII LIMITED VEGAS EDITION - The original mod
http://www.newvegasnexus.com/downloads/file.php?id=38539
There is a new modder that is reworking this gun, making it .50AE caliber. He likes my ideas, so he's making this gun more like the "Lucky" revolver.
Re Cal of Limited Edition Deagle VII - As of this date, still a work in progress. The author said he's getting a new computer this week and will continue to work on this update.
http://www.newvegasnexus.com/downloads/file.php?id=43356[/spoiler:b774d2f5d6]
These lists are by no means exhaustive. For the curious, as others have done, here is a full list of mod files I'm currently using.
[spoiler:b774d2f5d6]FalloutNV.esm
Advanced Recon Tech.esm
Inventory Access.esm
Lings.esm
IWR.esm
Military NV Backpacks.esm
Decrucifixion.esm
BoulderCityFaceliftProject.esm
Caliber.esm
Goodsprings Filler.esp
BCFollowersClinic.esp
SadiesSundries.esp
WildBillsPawnArmory.esp
Better forest.esp
deserthouse.esp
EmergencyBunker.esp
EVault.esp
Freeside Food & Supplies.esp
Jacobstown Expanded.esp
Novac Compound.esp
NV Interiors - Cottonwood Cove.esp
NV Interiors - El Ray Motel.esp
NV Interiors - West Vegas Fringe.esp
searchlight_eng.esp
Water Tower V5, Special Edition.esp
Under Tower Storage.esp
WorkingCrimsonCaravanTraders.esp
WyattsHardwareStore.esp
Yormars Attire and Goods.esp
31 New Food Items.esp
Cliff's Empty Drinkable Bottles.esp
FalloutNVCheatTerminal.esp
FNV_MoreVendorCaps.esp
FoodSanitizerModv1.5.esp
Military NV Backpacks - BumBagUseSlot1.esp
MoreSkillBooks.esp
SkillBksBox.esp
MRE's.esp
Perky Snowglobes.esp
Ranger Denali.esp
RepairKit.esp
Starter Pack.esp
Improved Stealth Boy Eng v2.esp
NVsunglassesCateyev2.esp
WETS NV Space Suit.esp
ULBonVivantNotStealing.esp
Casino Exchange All.esp
CounterfeitBottleCap.esp
GomorrahProstituteEnable.esp
Oven Cooking.esp
populatedcasino-light.esp
Primm_Rumor_Fix.esp
Static Battery Replacer.esp
Stocked38 .esp
Ultra-Luxe slot machines - v1.1.esp
weathersnotstuck.esp
ED-E Stealth 2.0.esp
Light Step ED-E.esp
faster and better ED-E.esp
Raul Repairs Everywhere - Free Repair.esp
AllCompanionsEssential 2.0.esp
Comp_Idles_NV.esp
dressup.esp
ImprovedCompanions.esp
ArtsAndCrafts.esp
antitoxin.esp
LFox Bottle That Water.esp
ColdTurkey.esp
Decrucifixion.esp
ExplosivesRecipes.esp
HandyRecipes.esp
jerky.esp
LootableOldCars.esp
Craft Overhaul 1.1.esp
aaaJNFSniperZooming.esp
Better Sneak.esp
Better Tag Skills.esp
Jump Fall Fixer.esp
Kobu's Primary Attributes Uncapper.esp
MrSlackPants-DecentPipboyLightNV.esp
Disable PipBoy Glove.esp
hold_breath.esp
Hold Out Weapons Expanded.esp
Immersive Karma.esp
IWR - Rebuilt.esp
Karma-Less Petty Crime NV.esp
maxres100.esp
Mod Loot - 2. Reasonably Rare.esp
Neck-id Slaves All Adults.esp
No Weapon Decay.esp
NoShirt.esp
PerkEveryLevel.esp
Max Level 100.esp
Poked - Survival 1.02.esp.esp
Power Armor Training Perk.esp
ShotgunPerformance.esp
SPECIALer.esp
Extra Characters - Fiends Quest ENABLED.esp
CONELRAD 640-1240.esp
SecretStash80.esp
RCSS.esp
StealthArmorFix.esp
Advanced Recon Armor.esp
Advanced Recon Gear.esp
Advanced Recon Tech.esp
Powered Power Armor.esp
Nevada Skies.esp
PlayAfterMQ_v1.esp
Faster Runing +25%.esp
BathFix.esp
TorresFix.esp
127mmBreakdownFix.esp
Benny's Lucky Lighter.esp
Improved Casinos 4X.esp
CasinoBankMoney.esp
I Got Spurs.esp
Unique Items & Col_NOBONUS.esp
NoCombatMusic.esp
L38UpgradeTerminal.esp
TimeCapsule.esp
Brotherhood and House Alliance.esp
Classic M72 Gauss Rifle.esp
Classic M72 Gauss Rifle (Fixed VATS DMG).esp
Moddable Unique Weps.esp
Plausible Starting Outfit.esp
Goodsprings Cozy House.esp
Homeless in GS.esp
MakHealOther.esp
NiptonRevisited.esp
Total active plugins: 129[/spoiler:b774d2f5d6]
Happy modding!
EDIT - A couple of new additions to the highly desirable list:
Afterschool Special - The Goodsprings Schoolhouse is first encountered in it's vanilla state, exactly as presented in the original game. The difference is that there is a repair shop across the road. The two people there are voiced and well done. They help you gradually rebuild the schoolhouse in a series of quests, instead of just shoving a fully functional "Player Home" into the game. NOTE: There is a small conflict with Goodsprings Filler. The repair shop covers a locked basement entrance requiring a key. Getting the key requires the Courier to choose being a jerk. It's not necessary to complete the involved quest anyway.
http://www.newvegasnexus.com/downloads/file.php?id=43757
Desert Eagle - Adds the Desert Eagle, Mark XIX, to the game in .357, .44 magnum, and .50 AE (requires the CaliberX mod). One caliber can be rechambered to another, if desired. The models are well done and the weapons are quite effective. Can be found on enemies or purchased from merchants. Also adds some unique pistols called "Desert Dragoons".
http://www.newvegasnexus.com/downloads/file.php?id=36151