Not sure, but I just checked and I have upwards of 3700 unfinished MIDI files I've authored over the past 20+ years -- more than 8MB of data. A lot of that is multiple drafts of the same songs (e.g. one song might have 3~5 variants from a single session where I was experimenting and kept all of the drafts as separate files, and sometimes I came back to an idea and experimented with it again and again like that over a period of years). I also tend to keep a lot of my musical doodles.

There's a couple dozen pieces in there that I think might be worth the effort of going back to and finishing someday, maybe; everything else is just my musical research notes, basically.