Qaz from DCEmu (registration required) has released a pretty nice AIM/MSN/Yahoo client for the PSP. It's pretty easy to install and use ... so long as you're willing to struggle with the PSP's pathetic phone-like virtual keyboard. Too bad ZX81's newly released Virtual Keyboard isn't compatible: certainly, conversations would be far more manageable. Regardless, these are two appreciated apps that will certainly help a great number of people, especially because it doesn't involve homebrew. Simply download, extract, and access from the PSP's internet browser.