There are quite a few communities bustling away in the General Sociability forum, and some of those have produced of videos of their antics. I've embedded just a few of those below. There are many more, and I am sure others still I haven't seen.
Are you doing video stuff with the RPS community? Link your work/play in the comments!
ARPS and some other online Arma 2 types in a 70-man joint ops mission in Arma 2:
NS2 people playing the Faded mod for Natural Selection 2:
The Rock, Paper, Synapse guys commentating on Frozen Synapse league games:
The NC Planetside 2 guys:
Commentated DOTA 2 from the Absolute Bedlam Tournament