I'm dead serious here, but if you are working on something useless do anything in your power to change that. Never work on something that's for sure going to be useless. Sometimes things become useless later, or don't pan out, and that's fine. But you're dead in the water if you aren't in a position to avoid working on something you know is useless. In fact you really shouldn't be working on something that isn't the MOST useful thing you could be doing.