Ok here is my games for PSP:
Tekken DR
Ff Tactics TWOTL (Great game)
Tales of Eternia (One of best Rpg of all time)
Breath of fire 3
Final Fantasy 7 crisis core
Metal Gear Solid Portable Ops
GOW Chains of olympos

I would recomend:
Valkyrie Profile:Lenneth
Wipeouts
Syphon Filters
Patapons
Killzone Liberation
Megaman Maverick Hunter X

You can easily log in with your PS3 account once you have upgraded the firmware to version 5.

If you've got a PC on the net, download Media Manager 3 for PSP from Sony then access the PSN for demos through there

You don't need to make a new PSN account either, your PS3 one will work just fine and your wallet can be shared between the two platforms.

Also make sure to check out the media streaming capabilities of your PS3 through RemotePlay! (you'll have to pair up your PS3 and PSP first by USB though to make it work properly)

Speaking of pairing my PSP to my ps3. does the PSP usually come with any cables besides the charger? That's all I have.

No in-game XMB. Phail.

lol

I can't remember

But you can just use the same one that charges the PS3 controller (standard USB mini - USB cable)

OMFG there's a cookie theme! I'm sitting here eating chocolate chip cookies with milk. I'm a freaking cookie whore. I eat more cookies than cookie monster. This is perfect!

You can hook your PSP up to your 360... ohh wait.

There is lot of awesome themes for PSP..Just google PSP themes.
You have Mini Usb cable right?That which comes with cameras and you charge your Ps3 controller with it..You can put stuff on PS3 with it or from Ps3 to your PSP.
But no other cables come with PSP...

Yeah, I have the mini USB cable that came with the ps3.

@pbroy: You can hook your PSP up to your PS3... oh yeeeah.