I think my top 20 would go as follows (not including handhelds)

1. Sega Mega Drive
2. Sega Saturn
3. Atari Jaguar
4. Atari 7800 (also plays 2600 games)
5. NEC TurboGrafx
6. SNK Neo Geo
7. Sega Dreamcast
8. Sony PlayStation
9. Super Nintendo
10. Sega Master System
11. MB Vectrex
12. Atari XEGS
13. Philips CD-i
14. 3DO
15. Mattel Intellivision
16. Coleco Vision
17. Microsoft Xbox 360
18. Sony PlayStation 2
19. Nintendo NES
20. Nintendo 64

This is based on my own personal taste (as much of theirs seems to be). If I was doing it on some sort of historical signifcance/importance then then I would have the Atari 2600 at no.1 as although it wasn't the first it is the grand daddy of all consoles.

I havn't included consoles where I havn't played enough of their library like the PS3, Game Cube and original Xbox.

Good idea Laird.

It was hard to put an exact list together. I also clumped some systems together.

1. Sega Mega Drive Genesis (Master System adaptor, 32X and Sega CD)
2. Intellivision
3. Nintendo NES
4. Colecovision with expansion #1 (also plays 2600 games)
5. Sega DreamCast
6. Vectrex
7. TurboGrafx
8. Atari 5200/Atari 400 Computer (same just a few different games and different controllers)
9. 3DO
10. Commodore 64
11. Atari 7800
12. Atari jaguar
13. Nintendo GameCube (Gameboy adaptor)
14. Odyssey 2
15. Super NES
16. N64
17. Sega Saturn
18. Xbox 360
19. Playstation 2
20. Commodore Vic-20
21. Wii
22. Playstation I
23. Xbox

Handhelds

1. Sony PSP (game detail is incredible)
2. Atari Lynx (Ms. Pac-Man and Pac-Land in portable form, cannot ask for more)
3. Nintendo DS (Multi DS hook ups lead to trash talking racing games. Plus you can play GameBoy Advance games)
4. Nintendo GameBoy Color (Still some hidden gems to be discovered)
5. Sega GameGear ( It is made by Sega so I added it on as a filler)

Handhelds

1. Sony PSP (game detail is incredible)
2. Atari Lynx (Ms. Pac-Man and Pac-Land in portable form, cannot ask for more)
3. Nintendo DS (Multi DS hook ups lead to trash talking racing games. Plus you can play GameBoy Advance games)
4. Nintendo GameBoy Color (Still some hidden gems to be discovered)
5. Sega GameGear ( It is made by Sega so I added it on as a filler)

I suppose I better add mine then 

1. Atari Lynx
2. Neo Geo Pocket
3. Bandai Wonder Swan
4. Nintendo DS
5. Gameboy Advance

Nice hand held list

My top ten favorite consoles would probably be,

01. Dreamcast
02. Vectrex
03. Mega Drive
04. PC Engine Duo-R
05. PlayStation
06. PlayStation 3
07. Saturn
08. Wii
09. Jaguar
10. ColecoVision

My top five favourite handheld consoles would probably be,

1. Lynx
2. DS Lite
3. Nomad
4. Neo Geo Pocket Color
5. WonderSwan SwanCrystal

Nice to see the Sony consoles rank so high on your list 

1. Sega Mega Drive
2. SNK Neo Geo
3. NEC PC Engine
4. Sega Dreamcast
5. Sony PlayStation
6. Sega Master System
7. Super Nintendo
8. Amiga CD32
9. Sega Saturn
10. Microsoft Xbox 360
11. Microsoft Xbox
12. Nintendo 64
13. Nintendo NES
14. Nintendo Gamecube
15. Nintendo Wii
16. 3DO
17. Atari Jaguar
18. Philips CD-i
19. Sony PlayStation 2
20. Sony PlayStation 3

Handhelds

1. Nintendo Gameboy Advance
2. Sony PSP
3. NeoGeo Pocket
4. Atari Lynx 2
5. Nintendo DS Lite

@ Laird: Zip it, trollboy!

@ AmigaJay: Loving that you rated CD-i higher than PS2. Word!

@ Laird: Zip it, trollboy!

@ AmigaJay: Loving that you rated CD-i higher than PS2. Word!

So despite your claimed loathing of all things Sony you rate the PS1 and PS3 as better consoles than the Saturn and Jaguar and one of them makes your top 5

Can only comment on hardware i've owned, not emulated, in order to keep things fair, so no mention of PC Engine or Neo-Geo.

Starting with home consoles 1st, handhelds to follow:

1)Mega Drive:The right system at the right time, such a wide libary of stunning games.

2)Playstation 1-Just jaw dropping at the time, plus got me into Import games via the dark art of chipping.

3)Atari 2600, same situation as the MD for myself, seemed to be the console everyone owned, so you were never short of games as swapping loans with friends etc.

4)PS3-If only for things like Uncharted 1-3, KZ2+3, Demon's Souls+Valk.Chronicles, plus superb media device.

5)Xbox-The console that delivered what i expected from PS2!, even better when modded, but an untouched Xbox was a powerhouse of a gaming system.

6)Dreamcast-Lifespan cut far too short, some of it's most promising games never saw the light of day, but i still find it a superior piece of hardware to the PS2.

7)Xbox 360, great machine, handful of exclusives, but not liking path it's taken past 18 months and never found it's exclusives quite lived up to those on PS3.

Sega Saturn-Criminally under rated 3D wise as proved when hardware was written for,plus Baku Baku...so needs a PSN/XBLA update.

9)Game Cube, if only for:Twin Snakes, Res.Evil's 4+Remake, Eternal Darkness/Loathe the Gamepad.

10)Jaguar:would love to have placed higher, but so few people really wrote to the hardware itself, so as amazing as Tempest 2000, Iron Solider, Doom, AVP etc were, it needed so many more games of this calibre at the time to chart higher.

11)PS2 (only just made it this high up), still own mine, there are some amazing games out there for it, but...it never came close to the hype, picture quality is poor, looks washed out compared to DC, let down by limited texture Ram etc.

12)N64, close call between this and PS2 being here, loved Golden Eye, Perfect Dark, Lylat Wars but the A.A was too OTT in places and going with carts at time of CD dominance cost it dear.

13)Vectrex, bought as a curio, fell in love with it, sadly had to sell it.

14)Snes, yes it had more colours, better sound, but only ever found a handful of games that really stood out:Plok!, Lawnmower Man, Mr Do!, Alien 3+Choplifter 3.

15)MCD-when used, hardware was stunning, but far too much FMV dross, along with cart games with CD music+Intro.

16)32X, worst thing i bought, crude set up (plugs+leads all over the shop), Virtua Starwars was jerky, Metal Head too slow (even for a mech game) etc.

Hand Helds:

1)PSP-just such an amazing device a lion of a console, in the promotional hands of utter morons, sadly.

2)Atari Lynx-See above!.

3)Sega Game Gear, fantastic device, G.G Sonic, Shinobi, Lemmings etc plus the MS convertor, eye strain ahoy though with that poor LCD screen.

4)GB Micro-Superb quality screen, great line up of games, but it's size and my hands made it uncomfortable for long gaming periods, so i'd use GB Player on G.C instead.

5) GBA:Size wise more suited to myself, but non-backlit screen was a no-no.

6)Original GB-Given 1 as a gift, have a few games, but man, THAT damn screen, awful, just awful.

7)Neo Geo Colour Pocket-As of yet, never opened mine, nor tried any of it's games.

@ Laird: Zip it, trollboy!

@ AmigaJay: Loving that you rated CD-i higher than PS2. Word!

So despite your claimed loathing of all things Sony you rate the PS1 and PS3 as better consoles than the Saturn and Jaguar and one of them makes your top 5

Indeed! A Ninty console appears on each of my lists too but I'm a Ninty hater too, apparently.

I would'nt worry DC, over the years i've been called:

A Jaguar fanboy and later a Sony Fanboy, based on 1) My emails to a certain editor of a certain magazine over a certain article (sounds like plume.....) and 2)daring to point out that PS3 version of a game auctually is better than a 360 version, even Offical 360 magazine making note of in it's review.....

Can only comment on hardware i've owned, not emulated, in order to keep things fair, so no mention of PC Engine or Neo-Geo.

The only one i havent owned at some point of my life is the Neo-Geo, but i've owned a CD-Z so apart from the loading times and the odd cd track the games are identical, but id love a proper aes, maybe oneday.

Had it made it's way to the UK, i'd been all over the PC Engine, like a rat up a drain pipe.

Sadly, it did'nt so i was'nt.Shame, real shame....