Misteryo, the radiation info given by a game character is a great idea.
I was already planning to make Smiley tell you a little bit about radiation in the TC, and imagined something like this when you first met him:
"Man, am i glad to see you! *cough*"
"You're Smiley, right? Ardin sent me to get you. How did you end up here?"
"Well, i was going to see where all the golden geckos came from, so i went into this cave and climbed down the ladder. Next thing i knew, one of those goober-eyed so'vabitches, *cough*, he jumped out from behind me and took a snack-sized chunk out of my leg, made me lose my spear into one of those rad-puddles and all. Couldn't get back up, either, so i... well, i panicked. Ran like *cough*, like a Gecko on Jet, and ended up here. Yeah, that was a few days ago, too. My geiger counter's been crackling like a pig rat in a frying pan ever since, had to turn it off to get some sleep. I've been shootin' Rad-Away from that locker on the wall over there, which is prolly why i ain't puked out my liver yet. Anyway, will you help me out? *cough*"
"*You decide to give this pitiful, cowardly hunter a reproach* A real warrior picks up his spear when he drops it, whether the goo stings or not. Holy Geiger counters start ticking when a person has many spirits, every shaman has one to prove that he's in connection with their world. And why didn't you bring your own drugs if you need them so badly?"
"Oh, jeez. A tribal. Thank you for this, Ardin. Listen here, Raging Bull, I'm guessing that your shaman has you picking his favorite herbs near some glowing, green pools, his average garden variety weed is the man-eating dandelion and his hair fell off many seasons ago, now, am i right?"
"Uh..."
"Right. *cough* Now listen. Avoid those pools if you like your skin on. Yeah, we all heard that before, but it doesn't hurt to be careful. And i'm no dope fiend, goddammit! Rad-Away is a medicine that cleans your body from radiation. Radiation is a type of invisible poison gas that comes from weird animals, green puddles, and even from the earth itself, or so i've heard *cough*, and a geiger counter measures how much radiation you've soaked up, *he chuckles*, spirits, my ass. Now, there are other medicines and probably some armor that might protect you against radiation, but the smartest thing to do is to stay away from anything like this place, which is why we should both get going! Can you help me out?"
(250 exp for this info, that was a good idea)
The idea is that he sort of knows what radiation is and therefore carries a geiger counter, but no medicines against it since he doesn't take it very seriously until he realises how dangerous it is. After all, these are wastelanders, not highly educated people, and they don't usually believe in things that they can't see. Same thing with Puking Charlie in VC and people living next to a uranium mine, they just don't know better. The VC council, however, is worried.
You will also have a choice to give him Radaway after he's returned to Klamath, since you can notice that he's looking pale and still coughing, and he'll tell you that it's probably an aftereffect of the caves. He then feels much better an hour later and gives you his geiger counter, plus 100 karma:
"Hey, you're a notch smarter than any tribal i've met. Take this thing, will ya? You'll need it. *he gives you his geiger counter, which immediately starts crackling, so you turn it off.* I'm gonna stay a mile away from anything that glows after this."
Adding new characters and houses requires use of the mapper, which again requires Science 350% to use
I like Misteryo's dialogue, though.