Minor Setback

Earlier this week I was driving my Catera through the college parking lot and it suddenly died and lost all power assistance. (Braking, Steering, etc.) I had no idea what was going on, so I pushed it and let it set for a bit, then attempted to start it. It turns over just fine but won't start. Waited about 20 minutes, then tried again. Fired up as if there had never been a problem.

Tonight I went out and it stranded me 20 miles from school. After a bit of trying to start it, it fired up and drove home fine. I am curious as to suggestions for what the problem may be.

My first thought was the Crankshaft sensor but the dealer replaced that a few months ago when they did my heater valves, etc. Also, during standstill the car rough idles at times. Don't know if that's related or not. No codes are thrown up by the computer and no warning lights are on.