oo how could I have missed this thread!?
I absolutely love "The Guild" and this is the best they've done
Check out "Dr. Horribles Sing Along Blog" aswell if you enjoy "The Guild" (the web series that is not this music vid)
Felicia Day (red-head in video from OP) and Neil Patric Harris (Barney in 'How I met you mother') is starring in Dr. Horrible and I find it quite fun, it's only 3 short episodes aswell