Yesterday's PS3 firmware updates packs a nice little surprise Sony didn't mention - it enables PS1 gameplay via Remote Play on your PSP.
Just to clarify, that means that you can play PS1 games that are loaded onto your PS3 hard drive on your PSP via a wireless connection, including via the internet.
Why is this cool? Because you can stuff your PS3 hard drive full of PS1 games and play them wherever you are in the world, via the internet on your portable.
It works with PS1 game discs, too, but you'll obviously need to have loaded the disc into your PS3 before you left the house, unless you have a super game-loading robot at home that can do it for you.
You will need to have updated your PS3 to yesterdays 2.10 firmware first though, and your PSP will need firmware version 3.72 or later (3.80 was also released yesterday).