Sometimes if I get thoughts I can't get rid of, I will give them to one part of my mind to worry about, and let the worrying go on in the background, and use most of my brainpower for what I need it for at the moment (work, play, etc.). That way I can keep the thoughts in the background but allow them to express themselves instead of trying to suppress them. I think of it as like throwing a dog a bone to chew on.