I maintain http://metroidvanias.tumblr.com which is a list of Metroidvania-style games, and other games enjoyable to MV fans, available on PC.
Come on over if you're looking to find something to waste the rest of your weekend on! Click the #released tag to start downloading stuff asap, or the #indevelopment tag to see what's cooking in 2013.
* I know some don't like the MV word, but it's what I went with
* Not everything on the list will fit into your personal definition of MV, but I'm hoping you'll allow those few offences to pass