ChickHen R2 - allows you to enter HEN (homebrew enabled) mode on your PSP.

5.03 GEN-B - Allows for all the benefits of custom firmware.  Even launching of the new 5.50/6.00 protected games.

SeDnA Plugin - Allows your PSP to stay in GEN cfw, even after a reboot and prevents shutdown from vshmenu.

PSP States Plugin - Savestate on any PSP game or homebrew

PRX Launcher V2 - Allows you to activate any plugin in HEN/GEN mode

Music PRX Mod - Allows you to play custom soundtracks while playing any ISO or homebrew game.  This version of music.prx is specially modded to be compatible with 5.03 GEN

CXMB MOD - modified CXMB that will load 5.00m33 themes with out the need to patch them and use the 5.03 cxmb.  Unfortunately your current 5.03 themes will probably not work if you have run the 5.03 theme patcher on them already

Ultimate VSHMenu - The ultimate in vshmenu configuration also giving a proper working recovery menu accessible from XMB (not a true recovery menu that can be initiated pre-bootup)

HEN Flash Dumper - Allows you to dump your NAND in HEN/GEN.  WARNING - DO NOT EVER FLASH ANYTHING TO YOUR NAND.  IT WILL BRICK YOUR PSP !!!

gpSP 5.03 MOD - gpSP Gmeboy Advance emulator, specially modified to run under 5.03 HEN.

IR Shell Patch - A patch to allow IR Shell to run under C.F.W. Enabler - should work under 5.03 GEN too, but I haven't tested it...