C):{

It's a cowboy. Or just any guy with a mustache who wears a hat. Variations include : c):{, C):<, C):O, C)B, etc. Essentially, you can take any emoticon and put a hat on it. It's just that the mustache is cooler.

Guy 1: Hey, can you show me how to do a cowboy in text chat?

Guy 2: C):{.

Guy 1: Thanks bro!