Mod your racers on PSP
It took a good few months for LittleBigPlanet to make the (largely successful) jump from the PS3 to the PSP, but its vehicular equivalent isn't waiting around that long.
ModNation Racers has just been announced for the PSP and will include all the same features as its big brother, including online play.
There are no specific release dates for either game but they are due this year.