Be3f, An enterprising coder on the DCEmu forums, has discovered a way to run homebrew straight from the PSP Slim and Light's XMB (main menu). The theory is simple: Since the new PSP can run UMDs from its menu, converting a EBOOT.PBP and all the homebrew data into an ISO/CSO format should allow the unit to run it as well.

To convert the homebrew, you will need both PBP2ISO and UMDGen. First convert the homebrew into an ISO format using the first program, then run the second program to convert it to UMD. After that, you should be able to run the homebrew from the menu. Note though, that some people on the forums have reported that this trick didn't work for them, while others say it works just fine.

Download both programs and see if you can get your homebrew to run from XMB. Be sure to read the included documentation for whatever program you decide to use in order to avoid any problems.