The Picture(!) should give you a good general idea of what my facial expressions should be like when I am winning or losing (smug or filled with murderous rage if you prefer).
Seriously though, I try to keep a good sense of humour while playing. Being a mediocre coach at the very best its important for me to have fun when playing.
I generally don't tend to foul except in retaliation. Then again, never say never. *Grins maniacally
I've read the Bloodbowl novel and I found that it captured the spirit of the game pretty well and would probably suggest it to anyone on this site.
Outside of Bloodbowl, I've pretty much "retired" from wargaming, but I plan on making a comeback sometime in the distant future.