I do
Original N64
Sleek 4mb RAM upgrade with my expansion pak
2 controllers (+1 save and rumble pak)
Awesome games like:
Loz:Ocarina of Time
LoZ: Majora's Mask
Conker's Bad Fur day
Goldeneye
And i'm getting Super Smash Bros

I have many. My favourite is still my Sega Saturn although I have dusted off my N64 from time to time.

I have a NES, a Megadrive (aka Genesis), an Amiga CD-32 and a Playstation (if it counts as old-gen console).

I have a PS1 with a few games. I am not sure how far back you consider Old Gen, but I have a Gamecube and about 100+ games for it, 5 wireless controllers, 4 sets of bongos, dance mat, and various other addons.

I've got a PS1 with all the Spyros and a Gamecube with three games and a couple of dance mats. Older still I have an Amiga 500 (but I better not call that a console otherwise it'll make people here angry; but I kinda use it like a console)

I have an atari, gameboy colour and super nintendo

I have an N64, though I haven't laid eyes on it for a good 5+ years and have no idea where it is.
Ironically, there's been a PSOne a few metres from my head for about the same length of time, and I have no idea where it came from.

Gameboy (Fatboy) Clear, 2 Colour Gameboys (used to have original Grey Gameboy with Paper Boy Till my mother hid it and it hasn't been seen since), 2 Mega Drive/Genesis my First one's Connectors are dodgy, Nintendo 64 and a Gamecube
i actually ended up with Three Copies of Legend of Zelda - Original 64, Wind Waker Collectors Edition and a Special Promo that included Master Quest, MM and the Original two Zelda's
For your 64, See if you can find a copy of Perfect Dark, it likes a Spiritual Successor to Goldeneye - Never Mind that X360 Thing
Despite never owning a Super NES I actually own a Super Scoper as well

After my freshman year of college, I bought myself a little "present" for surviving: a super nintendo with a bunch of games. Its my baby now, and I cherish it very dearly. I honestly think that it is, and always will be, the greatest console ever built.

There is a MegaDrive and Saturn less than two meters away from me, a few dozen games for each. I also have a broken GameGear somewhere, but only about 4 games, as they were hard to find and I had not much cash back then.

I have few :P
Mega Drive
Dreamcast
Super Nintendo
Nintendo 64
I even still have my Amiga! (i know its not a console but damn its awesome)
But the dreamcast will always be my favourite console. I can't let go of it.

I never had consoles when I was young. It was recession time in early 90's in Finland so my family never had money for consoles. And once I got my first PC I never really looked back until recently. So far I've bought Dreamcast and PS2 to play some games that I really loved to play in stores or when I was visiting friends. No need to buy PS1 since PS2 plays those games too, but good old (S)NES is still something I might buy someday.

Apparently the original is coming to the 360
I've got a PS1 and original xbox, might even have my atari 2600 in the shed. Wish I had my original late 1970s pong ripoff console, that'd be awesome to play on a huge TV

I still have my Megadrive, N64, Gamecube, Wii (I know it's not an previous generation, but lets be honest - it's shite) and the old black xbox!
Happy memories!

NES
SNES
N64
PS1
PS2