Well we know of the PixelJunk series of games for the PlayStation 3, but recently Q-Games released a version of PixelJunk Monsters for the PSP and from early indications it might be the only title that gets ported, the reason, piracy. Apparently the game was
pirated immediately and while Q-Games president has said they will wait for more numbers it isn't looking good for more PixelJunk titles to hit the PlayStation Store for the PSP.
Sad thing too for PSP owners, they have some darn good titles, a PixelJunk Eden fan owner/fan myself and Monsters fan/soon to be owner although on the PlayStation 3.