Since May 2005 when Homebrews were first discovered to run on the PSP 1.00 firmware, the PSP has acquired many new purposes than just causally playing a game of SOCOM. These Homebrews can be coded for many different purposes, from changing the PSP’s MAC address to using it as a Graphing Calculator. Here is a list of the 5 that i believe are the most useful.
5. AFKIM

AFKIM stands for “Away From Keyboard Instant Messenger.” Many web-based instant messaging sites have appeared but running an application natively, like AFKIM, is always more desirable than visiting a web site for the needed service. AFKIM has an amazing feature that allows the user to connect an IR keyboard to type Instant Messages, turning your PSP into a small IM machine! AFKIM is the leader in Homebrew IM apps.
4. iR Commander
iR Commander is my favorite IR homebrew. This app allows the user to turn his PSP into a Universal Remote. So just imagine walking into your living room, turning on your: TV, Stereo, Cable Box, and any other device that uses IR as a communication medium. Also, try taking your PSP to the nearest sports bar and turn off their TVs during a football scoring run!
3. Pandora’s Battery

Pandora’s battery is one of the newer developments that has hit the PSP. Pandora’s Battery turns an ordinary PSP battery into one that the people at Sony would usually use to service the PSP. This battery can Un-Brick the PSP as well as downgrade the Firmware. The Un-Bricking feature proves quite useful for PSP hackers that, during downgrade, accidentally bricked the seemingly impenetrable firmware fortress that is the PSP.
2. Downgraders
These might be the most commonly used applications on the PSP. Downgraders do exactly what their name implies, take a PSP running a newer firmware (ex 3.03) and bringing it back down to a firmware to can run homebrews (ex 1.50). However, as the Firmwares get high and newer, the more complicated the downgrade process is. A PSP downgrade is usually the first measure that hackers preform to unlock the full capability of the PSP.
1. Custom 3.03OE-C
The Custom Firmware is another initiative that most hackers take. The custom firmware was created by possibly the most acclaimed PSP hacker Dark_AleX. The Firmware also allows the user to play homebrews that usually only the 1.50 firmware could play. But, since it’s running the 3.03 firmware, the user can access all the 3.03 features such as a Visualizer for the Music player.