OK - still don't know if 'hacked' is the term I'd use.
Have one-off light mounting installations on most of my bikes, a one-off helmet light mounting arrangement, a couple 10mm solid front axles installations, and some modified rack mounting installations. But none of that looks 'home-made'. A few other things might be unusual combinations, but are just stock parts used differently ie low ratio mtb cranksets on touring bikes or hybrids.
There are a couple homeless guys here that have built complete racks and platforms using hundreds of zipties and twigs though - is that more what you had in mind?