Prologues -- What's your opinion?

Prologues --- What's your opinion? 

Prologues usually annoy me, and I tend to skip them unless they are very very short. I realize they can serve a purpose, when used as quick intro to the back story, but at other times they seem like they give out way too much info. In general, I  prefer to learn the back story through flashbacks as I read.

• Do you like when an author uses a prologue?
• Do you prefer when a novel starts right in with Chapter 1?
• Do you not care one way or the other?