Glad to hear you didn't come a cropper. Nasty business, and bloody lucky it didn't do any damage.
Happened to me a few times when I was a skint despatch rider with cheap chains. One wrapped itself round the rear sprocket and locked the wheel....
Last time it happened I was doing about 100 on the Autoroute on the way back from the Nurburgring. It was the OEM chain on my Speed Triple. I went to adjust it before I left but realised I had no adjustment left (eccentric adjuster hub - not so easy to see how much adjustment remains).
About 30 miles away from Calais something went BANG and suddenly I had no drive. I thought it was the gearbox, as I was shifting down and getting nothing, but pulled up on the hard shoulder and realised the chain had fecked off.
Upon exiting the bike it had removed a lump out of the seat unit, gouged the underside of the pillion footrest, and destroyed my hugger. Fortunately it didn't touch my girlfriend though....
Scared the crap out of the poor bloke on a Hayabusa who was following me.
Nowadays I have a Scottoiler and keep a good eye on my chain!
Strayed off the point a bit there though - hope you get yours sorted and no doubt with a new one you'll have no problems.
Nik