Eversave, another daily deal site, has a free $5 credit just for signing up. Word on the street is that after December 31st, they will no longer be offering this credit. So if you haven't already, sign up to receive their daily deals and you'll get your $5 credit to be used in the next few months once you find a deal you like!
And as a side note, if you haven't signed up for Deals That Matter and received their free $5 credit, now would be a good time for that as well. Who knows when it will end!