Ooh Err Pop Bang

Ok, so, here's another one from the car killer. I Was driving along the Oxford ring road today, around 80mph (thought i'd be honest) and the engine just cut out, there wad a small chudder from the exhaust but apart from that just like i'd turned the key off! Is this something to worry about? I just put my foot on the clutch and started off again, left it in gear, then lifted the clutch. Then, the steering wheel warning light came on and the wheels woudn't turn... luckily the road was straight! To try to stop this i actually turned the engine off again and restarted... all was ok and has been since. Is this something to worry about?

Many thanks,

Duggie.