This might be a good time to show your opponent a text card, or maybe your one and only good card (provided it is one of the better cards)?
In otherwards; Junk in hand, you have one of the better cards. You place it down then pick it up and replace it with a junk card...It might keep your opponent off your back, [him] thinking you're trying to set him up, or it might just frighten him enough to be a bit more cautious.
Sometimes nothin can be a pretty cool hand.