I've combined ps2rd's cheating capabilities with a menu driven interface powered by GSKit. This will allow you to select individual cheats for any game in a list (like a normal cheat device). It supports all the code types ps2rd naively supports. Since I wanted to make this just for cheating, I've removed the debugger and LAN interfaces as they're not really needed. This was a project I wanted to tackle to strengthen my programming knowledge.
Update - September 2, 2013
I had some freetime over the past few days and made some updates to my cheating device GUI. It's more stable than previous releases and has had more unneeded parts of ps2rd removed (such as videomod). BOOT2 selecting now works as it should, so you can boot to a ELF instead of directly to disk. I've also added preliminary support for compressed code lists. Basically, you use the included "compress-decompress.exe" program to compress/decompress your cheat files using zlib compression. When using a compressed cheat list, it must have a file extension of ".bin" or else it will try to load it as text. Update ps2rd.conf to reflect whichever cheat list you're using. This should help cut down on loading times.
Fix delete option (currently does nothing)
Implement less-awkard cheat list compression (maybe use zip/7z files instead)
More code cleanup
PS2-side codelist manipulation (add/modify/delete/etc.)
If you find any bugs, please let me know!
Updated source code will be available soon. Source on github is not the latest version.