Backtrack

Backtrack lets you record all those conversations, calls, and brainstorming sessions that you forgot to click the record button for.

Backtrack is always on, and over-writes a 60 minute window of audio over and over throughout the day, locally on your Mac. As soon as something happens that you realize you should have recorded, just drag the icon down to the time you need to backtrack to, and the app will save an audio file to your desktop.