NB I have a japenese DS + buy all my games from Japan

- some of these games might not be out in england/us yet - not sure.
Hotel Dusk
Another Code (if it's cheap - it's awesome...but over in like 5 hours...)
Jump Ultimate Stars
Trauma Centre
Wonderful World
Phoenix wright
Professor Layton and the Curious Village
Zelda: phantom Hourglass
Elite Beat Agents
Fire Emblem
That's 10 awesome games off the top of my head - I can think of loads more - I'd say buy a DS. But I don't have a PSP so I may be slightly biased.