Jeez I can't believe a thread this huge & old has slipped me by till now! It's older than I am:P
Well... I always feel the best games are the ones you write yourself. They're crappy and buggy and whatever, but there's just something about making things with your own hands.
So waaaaay back when I was a teen I quote quite a few little games in Basic on my Vic-20 and later Apple-IIc. The Vic had 3.5k of RAM (that's kilobytes, not megs) and no disk drive, not even a floppy... mass storage was on cassette tape. The Apple had a whopping 128k RAM with a 140k floppy drive.
Meh it wasn't much, but it was all we had, and I made some cool little games. There was space shooters, and asteroid dodging, text adventure, ASCII adventure, poker machine, card games.....
Incidentally I still have the Apple and my original disks with me today.... I uploaded the disks to my PC to use them in an Apple emulator, so they're safe forever:)Maybe I should post some screenies:P
These days I still try to keep my coding skills up, but of course I've moved on to Java and w/e.