If you're on a Mac, you may get a kick out of
Delicous Library. It manages books, movies, and videogames, and hooks into Amazon's API in order to deliver *whatever* information they have on the item in question.... including cover artwork, platform, synopsis.
Pros:
-VERY easy to use
-Gives you a "virtual bookshelf" of your items
-Handles movies and books too
-+++use your webcam as a barcode scanner
-Gives cover images when available
Cons:
-Doesn't deal well with the vagaries of games.... for example, you can't make your PS1 longbox games look like longboxes, unless you intentionally mis-label them.
-Haven't found option for scanning/importing your own cover images.
-Gets information from Amazon, so expect it to work with N64, PS1, Dreamcast and forward. NES, SNES, Genesis..... not so much.
-sometimes mis-identifies games, system, cover, etc.
Honestly, it's a good way to quickly enter your collection into an organized format. I give it bonus points for easily also handling books and movies. I'm looking for something better though, something more game-centric which accounts for the peculiarities of being a game collector. Something like freedb for games, with support for cover artwork and ability to export to multiple formats like csv.