Personally, I'm preferential to the soundtracks of Homestuck (from this website) and TowerFall Ascension (2 links). If I had to go with a single track from each, I'd pick Eternity Served Cold and Frostfang Footslip. If you've never heard of either, check them out! Homestuck has the added bonus of being entirely free to access. EDIT: links actually work now. Oops.
I was a little drunk when i made this thread, this song is not even that good. Really love the soundtrack of the IOS game ALONE.