I stole this idea from the YALSA listserv (which, if you're not familiar with it, is a great resource, both for discussing YA lit and getting other library ideas--go to the ala.org page, select YALSA, and find their professional resources page). Anyway, the following discussion came up: how to promote great books with hideous or stupid covers??? I thought these were great ideas:

collaborate with the art teacher to have kids read books with ugly covers and then design new covers for them.