I am currently looking into how much flash is supported by the PSP
It as a custome version of flash 6.
The keys that seem to be linked are:
the dpad are to their respected keyboard keys
the X button is linked to a mouse left click
It might not seem like much but "the smalled website in the world" http://www.guimp.com really does show off what the psp can handle games wise.
Also I am currently trying to figure out if the psp accepts MP3 streams and Dynamic pictures which were solidified in flash 6. If it can some interesting apps can be created if you have the imaginiation.
Currently homestarrunner works alright with the psp, the sound is clear but the processing power is lacking so it will skip frames to stablize. many other flash animtions work as well... the problem is most are too big for the flash screen.
I for one am going to try to develope games/apps specifically for the PSP, even if every one complains about how little it does compaired with a PC running flash 8. (other websites)