Youtube: I post oscilloscope views of chiptunes from other composers or myself and sometimes other stuff.
Reddit: I'm only there to post stuff in the bytebeat subreddit. I don't plan to do anything else on reddit in order to preserve my sanity.
Github: Not much to find there, apart from a collection of every song I made in bytebat.
CSDB: My C64 stuff, only music for the moment.