Lurker here (and thank you ladies for all the freebie links you provide!) but here are my other sources for freebies...
and Digital Book Today (both also send daily emails)
Mixed genre, and apologies if they are full of affiliate links, I'm a Kindle newb and don't actually know what an affiliate link looks like... or how one makes money off free books?!
I've tried a few searches, both by price and using terms like "save 100%" etc. - but wow, you need a lot of time to sift through it all!