Zachariah Scott, a cinematic designer at BioWare, may have an unfair advantage when it comes to Source Filmmaker clips, seeing as he's not exactly an amatuer, but whatever. If professional videos are what we get when professionals use the tool, then we're all winners.
In this clip, TF2's Medic has an...episode after the loss of his beloved bird. It's far more haunting than I would have thought before I pressed play.
Bad Medicine [YouTube]