Sega Genesis - My baby. This is the system I grew up with and the one I share the most memories with. I have a pretty good collection of games, most of them a good joy to play. Great memories with Sonic the Hedgehog, World of Illusion, and others.
Nintendo Entertainment System - The first true system I remember ever playing. It was given to me by my first father and it's a system I have fond memories of. Good games & such. However, as is the case with most Nintendo systems, the passion just isn't there for me.
Super Nintendo - Got it for my birthday in the early 90s. An ok system, but only have about 4 games for it. Aside from Super Mario World, never had THAT much fun with it.
Sony Playstation - The system that probably reintroduced gaming to me, 2nd only to the Genesis. Lots of good memories with it, thanks to Spyro the Dragon and NASCAR.
Sony Playstation 2 - Great system, plenty of fun. Sly Cooper, Rathet & Clank, Final Fantasy VII, and others.
Atari Jaguar - System that attracted me, thanks to it's cult staus. Now that I have one, love it too death. AvP, Canon Fodder, Tempest 2000, and Super Burnout are all games that I enjoy and count among my favorites of all time.
Sega Dreamcast - The system that I wanted most, aside from the Jag. Just got it a month ago and I'm slowly building up a library of games. Both of the Sonic Adventure games are great fun. I see great potential for this machine, like I do with the Jaguar.