I made something in source filmmaker in celebration of Cirno Day, but I don't know if I should share it due to it only containing two Touhou characters. (Cirno and Suika, the rest of the characters are from Team Fortress 2 and Mass Effect.)
If people want to see it
and can convince me that it belongs in this thread I will share it.
Otherwise, happy Cirno Day:
http://www.youtube.com/watch?v=xa6ppkrSTdY - Cirno doing "complicated" math.
http://www.youtube.com/watch?v=SCsO5W2hjqU - Cirno asks what air is.