I took a peek at my tank last week and caught my yellow watchmen goby feasting on an unlikely meal. He was eating a bristleworm which I didn't ever expect to see. It was pretty interesting to see as you could see all of the bristles stuck around the outside of his mouth. Here are a couple snapshots along with a link to the video I posted on youtube.
http://www.youtube.com/watch?v=AST_YVQtdzQ
http://www.youtube.com/watch?v=AST_YVQtdzQ