Maybe ebay or some domain auction would get you some traction. Also, not to put too fine a point on it I don't think they're very strong names, the only exceptions are slowdance.co.uk, and jkz.in, that has to be worth something more than 5 pounds to someone in India.

Did you have any specific project / reason in mind when registering these ? If so maybe you should add that so that the name can be placed in some context, like you did with the 'bec.ause'.