Over the past few weeks, the homebrew community has been working hard on a new exploit in PSP firmware that would allow users of PSPs 2.0+ (including the recently released 2.80) run homebrew without Grand Theft Auto: Liberty City Stories. NOPx86, a team of coders, worked to take advantage of a flaw in libtiff. What that means is that the potential for homebrew is here: and it's easy as well. The team released a "Hello World" application as a proof of concept, and you can try it out yourself here. Just extract the image, place it in PSP's PHOTO directory, and then try to view the image. You'll see the homebrew message working, even on a 2.80 PSP!
This is absolutely fantastic, especially because of how incredibly easy this is. Try it out, and who knows what kind of exciting new developments we'll see?