I'm personally hoarding a lot of NES and Atari games. They seem to have a really healthy return. Also keep your eye out for any RPG games..especially PS1/PS2 games. I have made hundreds of dollars on selling them in the past.
NES games are almost always a good bet, ESPECIALLY if they are complete in their original box.
Atari games aren't as hot as most think as there were so many produces, so unless you're getting a good bulk deal or finding a few of the rarer titles, they can be hit or miss.
Some general rules concerning video games:
BOXES BOXES BOXES. If the games come with the original boxes, this will at least double their value. Sealed boxes are bonus.
RPG (Role Playing Games) and most Sci-Fi games are hot and it's hard to go wrong here.
AVOID sports titles. Unless you're really lucky and find a rare title, these DO NOT SELL well.
Bulk. It's better to buy games in bulk. You'll get a better price and enhance your odds of picking up a rare or two.
Don't ignore computer games, especially again in boxes. The older, the better. CD Rom games are hit and miss where most floppy disk games are getting harder to find. Computer games to keep an eye out for are Commodore, Amiga, Apple II and even some IBM/PC games have value. In my spare time (that's a joke, BTW), I should start a thread about this ...
For instance, here's a recent Commodore 64 sealed game I sold (bought for $1 at a resale shop):
Carriers Force by SSI SEALED Big Box Commodore 64 | eBay
