Most frustrating would be Final Fantasy X-2. I am an advocate of levelling up as much as possible. In this game I got all characters to their maxium level, got to the last area (I think it was last) and was easily killed off by the first monster I met. I have not touched the game since.
Time Splitters; Future Perfect "made" me get an Xbox controller into a state where it needed some surgery. It does appear to still be working OK though!!
Recent (or still waiting for) purchases on Gamecube are Chibi Robo, Pikmin 2, Mario Party 6, Eggo Mania, Pokemon XD: Gale of Darkness and Odama. All pre-owned, or a sale item. Pikmin 2 was pre-owned, but still sealed!
Disgaea saw me putting over 400 hours of play into the game (3 times through... for the moment).
The Gran Turismo outings on the PS2 should also get an honorable mention as I like car racing games.
I suppose having completed a game (there have not been many) ought to count for something which would give us:
Xbox
Halo
Brute Force
Jade Empire
PS2
Phantom Brave
Makai Kingdom
If there are any more titles I have finished they are obviously nowhere near as memorable.
I think I would go for the GBA SP as well. If the releases on the DS continue with the innovative titles that seem to appear regularly I may be forced to change my mind.
I was reminded of this game the other day by seeing a topic about it at another forum. I only got about 13 hours into the Gamecube version. Was looking for the temple on the Southern Continent. I probably got distracted (that plus the fact that it was not that long after I finished the game on the DC in 100+ hours). Must really return to it so that I can see the extra bits brought in for the GC version.
Atari 2600 (or whatever it was called)
Spectrum
Spectrum 128
Atari 800XL
Atari 130 XE
Atari 65 XE Game system
Commodore 64
Atari 520 STFM
Amiga A500
Amiga A1200 (with 85 Mb Hard Disk)
Atari Lynx
Gameboy
Megadrive
Playstation
N64
Game Boy Colour (Pikachu Edition)
Saturn
Dreamcast
Game Boy Advance
Game Boy Advance SP
PS2 (old style slightly unreliable one with a flip-top conversion and an Asian, an American and a PAL slimline)
Gamecube
Xbox
DS
PSP