I do mostly pencil sketches on all my school papers and sometimes my sketchbook if I feel confident enough. I also use GIMP a lot to enhance these sketches into nice things, although I mostly use it to make really cool lab report diagrams.
I also make music found on the website below (haven't posted in a very long time, but I'm still really active playing piano and I'm learning to transcribe by ear). I use my art skills there too to make album artwork, I guess.