Books have been mentioned. I can pinpoint several books in my collection just by their smell alone. I guess I love it. When I read them, where I read them... Weird.
As far as video games go, yeah, there's this sort of snack which I used to chew on a lot while playing FO2. Specifically, it reminds me of New Reno. I guess, however, that's more of a taste induced nostalgia, and it's not real nostalgia either, just few simple memories. No real emotional attachment, even though I love FO2.
Smell of video game boxes is of particular interest. Most of the video games I own came in those generic plastic DVD cases. Strangely enough, I remember the smell of some of these boxes when opened, as well as the CDs/manuals within. This is especially true for Warcraft III Reign of Chaos. Always brings me back. The Culling of Stratholme. The discovery of Frostmourne. Horde voyaging westward to Kalimdor. Burning Legion under the burning sky. Battle at Mt. Hyjal. Not sure if I got all the names right, it's been years since I've played the game, but I loved it. There are several more instances - I've had one with CnC games too - but I guess nothing beats the smell of WCIII. That box does have a pretty strong odor.
Smell of glue and paint brings me back to those sweet, rare moments when I could devote myself to modelling, but those moments, although few, are scattered throughout the past years, so I cannot pinpoint a specific time or a model which I assembled.
I won't go into details with various "general" smells - freshly cut grass, summer rain, frozen winter nights and days of sunbathed snow with their fresh, chilly breeze in nostrils, ozone after a thunderstorm, heavy mountain air, various trees in various forests, earth and mud, the odor of some animals and plants, smell of certain tasty dishes and drinks, gasoline and machine oil and so on. Some of the smells are not so "nice" - smell of rotten flesh, human or animal, can bring back some unpleasant, or in the former case, even pleasant memories. I guess that sounds weird.
Several perfumes, deodorants etc. reminding me of past relationships, certain moments or just periods in life where I/a person close to me used them.
All of these trigger various memory/emotion responses for me linked with many images of my past. Sometimes specific, sometimes general. I guess that happens with most of the people tho.
There are many, many other memories which I can associate with smell, but it's hardly ever the smell alone.