Anybody ever hear of "Santa Muerte"?

Last week I went shopping for religious candles for my mom (the ones you see in Mexican grocery sections with Jesus, Mary, St. Jude, etc.) One really stood out to me, with its rather grim picture standing out amongst the other candles. I do a little internet searching and it turns out it’s Santa Muerte, a Mexican folk saint. Many claimed it is especially liked by drug dealers or even that it is used in Satanic rites. Anyone ever heard of it or knows the back story?

Santa Muerte

Note that some of the names listed (such as La Flaca, the thin one) are used to refer to Death without it being necessarily to this version.