I've always just given my current salary when I'm asked about compensation. Yes, it somewhat anchors me, but it ensures that the recruiters / company I'm talking to and I aren't wasting our time and it doesn't force me to give a range.

Also, don't be afraid to walk away from a position if they're under cutting you. My current role did that; I told them no. They called back a day later and brought me in at a higher position with higher pay (but oddly enough no real change in responsibilities)