I had the hydraulic pump belt break when I was about 30 or 40 miles from home, and of course I had a water pump belt and an alternator belt, but not the hydraulic pump belt.

The brake and regulator accumulators were both nice and new though so the "low brake pressure stop immediately" warning only came on about two or three miles from home (once there's no pressure at all, there's no brakes at all, but this is pretty difficult to achieve in practice) and I just had to cope with the twitchy steering through the difficult part - driving through town at 15-20mph in rush hour traffic anyway.