I posted some of Rob's music on the old forum and he's still doing interesting stuff. Recently, he's been doing musical challenges and producing songs that have no business sounding good considering the constraints on them.
Only using one fret:
Touching every fret:
14th fret capo (pins the strings to a very high fret, greatly reducing the number of notes available):
Deaf metal (skip to 5 minutes to hear him actually play it):