Home consoles:
PS1/N64
PS2
360 (for only 1 year)
PS3

Handhelds:
Gameboy
Gameboy colour
Gameboy advance SP
PSP
PSVITA (soon)

GBC (2000) - sold it in 2004
GBA (2001) - sold it in 2006
GC (2002) - sold it in 2007
GBA SP (2003) - still have, but will get rid of soon with GB/C games on 3DS eshop
PS2 (2004) - still have
DS phat and GBA Micro (2005) - still have both
Wii (2006) - still have
DS lite (2007) - still have
PS3 (2008) - still have
DSi (2009) - still have
NTSC PSX (2010) - still have
3DS (2011) - still have

Mega Drive
Game Boy
PS1
GBA
PS2
PSP
Wii

I still have all of them, but my PS2 is a replacement of one which broke within warranty and I don't have a working controller for the Mega Drive anymore.

SNES---- missing in action
PS1---- dead and discarded
PSOne
PS2
PC
PSP 2000 -----lost/stolen
PS3
PS2 3000

Handheld Console:
Nintendo DS (original non-lite)

Home Consoles:
Atari 2600
NES
SNES
N64 (black)
Gamecube (purple)
PS2 (original non-slim)
Xbox 360 (original 20GB)
Wii
PS3 Slim (120GB)
Xbox 360 Slim (4GB)

I currently still own the PS3 and 360 Slim consoles.  The next purchase will most likely be a Wii U.

Gameboy
Gameboy Colour
PC
Sega Megadrive
Xbox
Xbox 360

Just for interest I'll put the number of new titles I bought from a retailer in brackets.

1989 - NES (?)

1995 - Megadrive (4 - I scored tons of games off this kid at school)

1997 - PSOne (15)

2001 - GB Advance (2)

2001 - PS2 (12)
2002 - Gamecube (15)
2004 - Xbox (9)

2009 - Wii (8)
2009 - PS3 (14)
2009 - Xbox 360 (3)

NES(doesn't work right)
PS1(i have no idea where it is)
SNES(still playable)
Every thing SEGA except dreamcast(no idea where they are)
360(i never play it often enough to mention)
PS2(fell 10 times then stopped working about 3 yr.'s later)
Xbox(disc tray broke. i still hate Halo)
N64(got stole)
PS3(fell last wk. still works)

no portables

Pegasus (the Famicom/NES clone - very popular in Poland in early 90' http://en.wikipedia.org/wiki/Pegasus_%28console%29 )
PS1 (still working!)
PS2 - sold it
GBA - sold it
PSP
X360 (second one, first one RRODed)
PS3 (just bought it for this Christmas)

ipod touch - well counts as a heldhand

No handhelds for me.

Home consoles:
-Mega Drive (1992) (I wanted a Master System II, but my father bought the Mega Drive. Better for me!)
-Snes (?)
-PSOne (yes, the smaller and rounder PS1. I don't remember when we got it)
-PS2 (I don't remember when we got it, but I know the first games my brother an I bought were Tekken Tag Tournament and GT3, both platinum)
-GameCube (?. Bought it second hand with Metroid Prime and Super Mario Sunshine)
-Wii (December 2006)
-Xbox 360 (November 2009)