1988 - NES - my first console, a christmas present
1991 - Mega Drive/CD - my second console, which I would end up using well into the 5th generation, alongside ...
1994? - PC (Mac PowerPC 603e) - for most of my teens this was my gaming pc, even though it was a Mac and there wasn't a whole lot of games available. the lack of 3d acceleration really hurt it once games like Unreal came along.
1999 - PC (P3 450GHz, RIVA TNT 2) - a decent machine I got for college. Not a full-fledged gaming rig though, so it got outdated pretty quickly.
2003 - PC (P4 3000GHz, Radeon 9800XT) - this was an absolute beast back then it and served me well until the 7th console gen started and it could no longer keep up, leading to me buying a ...
2006 - PS3 - First console since 1991, a 60gb fat model with the juicy full backwards compatibility so I could sample some of the stuff I missed in the last two generations.
2008 - NDS - I wanted a handheld to make those commutes pass by a little faster.
2008 - PSP - I added a second handheld because why not?
2008-12 Gamecube, PS2, Xbox, Dreamcast, N64 & GBA - all systems I got secondhand over the course of the 7th gen so I could play what I missed that my PS3 wouldn't let me.
2012 - Xbox360 - Got it late in the 7th gen for the exclusives.
2013 - Wii - Friend wanted to get rid of it, so I took it off his hands.
2013 - 3DS - I'd grown quite fond of Nintendo handheld by now, so I got this a couple months ago.
2013 - Laptop (i7 3360k, GTX660m) - Meant for work, so gaming was just an added benefit, but it does quite well. It's mostly for indie games anyway, so I don't really need a powerhouse.