Our process has the customer to sign off on every completed card as the final step. We thought it would be pretty cool if we could have some kind of celbratory sound play somewhere when we get the signoff (similar to the concept of playing sounds when the CI build breaks/succeeds).
Obviously, Mingle doesn't have this out of the box, so we'll have to rig up a solution. The question we're dealing with is what the best way to get the information out of Mingle and into something that can trigger playing an audio file would be.
The RSS concept seems promising, but we want to make sure we're only catching the "signed off" events, and ideally that it's a short hop to actually playing the audio file.