What consoles do you have multiples of, and how did you acquire them?
Atari 2600 (5): I have five Ataris (not including the Flashback, Flackback 2, or the 10-in-1 joystick). The reason is simple; they're all different. Six switch woodie, four switch woodie, Darth Vader, and two Atari 2600 Juniors (long and short rainbow, one in the box). Only one (six switch woody) is hooked up.
Sega Genesis (11): As you may have read, for a summer I bought every sub-$5 Sega Genesis I could find. I ended up with about 14 of them. Now I have seven or eight Genny 2's, two Genny model ones (one in the box) and one Genny 3. Two are hooked up; One model II (which has a Multi Game Hunter copier connected) and the model 3 (with a Tototek Flash card).
Dreamcast (5): I still have my original Dreamcast, plus one I bought from a co-worker. Then I bought two from someone online because I was going to mount one in my car (never happened). Recently I picked a fifth one up from a thrift store, a black sports model for $7.50. Only one's hooked up -- the black one.
PSX (6): Two modded ones, a blue dev unit, and three "spares" (ran across them for under $10 each). Only one modded one is hooked up.
NES (5): One's my original one from back in the day, one's my wife's I've picked up the others from here and there for a couple of bucks. My original is hooked up, although usually I end up playing on my Famiclone (not included in the 5).
Nintendo 64 (6): One's my original one, then two came with console copiers that I've bought. Bought one from Kamino before OVGE last year (a green one), and recently picked up two in a trade. Three are hooked up right now, one with a V64, one with a CD64, and one with a Z64.
Gamecube (2): One blue one, one black one. Only the black one is hooked up.
PS2 (2): One launch one, modded (still no DRE's) and another one I recently got in a trade. Only the modded one is hooked up.
SNES (2): One original model, one SNES II. Both are hooked up and have copiers connected to them, a Super Wildcard DX and a Super Pro Fighter.
Commodore 64 (5?) / Apple II (3): I keep buying these as I run across them, putting together complete working systems and whatnot.
So let's hear about your multiple consoles? How and why did you get them, and why haven't you got rid of them yet?