As much as I love the PlayStation Network on my PS3, what with my heavy addiction to flOw, there was one slight issue with it up until today, namely that you needed a PlayStation 3 to access the content and transfer it to a PSP. You'll notice I say until today because Sony has now launched the service onto the PC opening up the haven of games and other content to a significantly wider audience.
At this time the PC based content is all PSP-only, Sony isn't giving away an emulator - as much as I yearn for one. The service uses the same database as the PS3 store so you can either use your existing login or, if you don't own a console, make a new one. Funds are then transferred to your wallet using the novel concept of pricing content in actual currency rather than lollipops and moonbeams, or whatever arbitrary system it is that Microsoft and Nintendo use. What's good about sharing logins with the PS3 is that content bought on the PC is available to the PS3 and vice versa.
On the subject of actual gaming content, classic titles such as WipEout, Syphon Filter and the original Crash Bandicoot cost £3.49 a piece and actually translate to the PSP pretty well. I feel almost embarrassed to admit it, but I actually stopped playing Assassins Creed last night in order to get a quick game of Crash Team Racing in. If games aren't your thing there are also trailers available in PSP friendly formats (none of that pesky re-encoding) and various backgrounds and themes to customise the menu if that floats your boat. Now if I can just get the Wii's virtual console on my DS somehow I'll be entirely happy.