Sony has announced that their PSP portable gaming device will not only have WiFi for online gaming, but it will also be able to use ad-hoc mode to connect to up to 16 nearby PSPs without the need for a wireless access point. This would be a heck of a lot easier than lugging PS2s and TVs around for a multiplayer session.
Also, I’m not sure why we’d need this, but “Sony reps also confirmed that the PSP will be able to connect to the PlayStation 2 through its USB port”. If I recall, Nintendo also did this with the Gamecube and Gameboy. Might be another one of those things that are hugely popular and well supported in the Asian markets, but a fizzer in US/Europe. Or perhaps they’ll extend the USB capabilities to allow MP3 (or rather ATRAC) files onto the PSP so it can double as a media player?