Newegg has Hd 280 Pro Sennheisers for $60 off, but today only unfortunately (2011-01-21)
The popular consensus here seems to be AKG K-240's I suppose, but man, brain stuck doing loops in trying to figure out what to do at this price and one day left. The pressure.. mounting!!!!
Perhaps the wrong place to post a deal like this (this thread seems to be more targeted to longer deals), but just in case this can help anyone stumbling on this post who doesn't obsessive compulsively hound Slickdeals