Had this happen when I was out on the road bike earlier:
www.youtube.com/watch?v=E07uKBiubDU
There was a pretty loud bang when it happened and it blew one side of the tyre right off the rim. Didn't cause any real problem where it actually happened, but a few minutes earlier I'd been descending a bumpy road at nearly 40mph, so glad it didn't happen then!
I've never had a bicycle tyre actually blow-out like that before - anyone else had that happen to them?

