[PanJet]

That's awesome. I've had that happen to me twice. Once I was decending into a valley and couldn't hear ATC handing me off, so a Horizon flight relayed the message.

Another time, a friend and I had lost our alternator and our battery was quickly dying while we were on an IFR plan at night (luckily not IMC). The radios were weakening, so we couldn't hear or transmit to center anymore, but we heard an Alaska Airlines flight, so we called them up and they were more than happy to relay our messages until they got us close enough to approach control where we diverted to.

The coolest part of that story is that the airport we diverted to, YKM, (Yakima, WA), kept their tower open an extra 20 minutes past their normal closing time to wait for us and make sure we made it safe. It was awesome how helpful everyone was that night.