Intermittent D2 won't start.

Last week I drove my truck into town 5 miles away. I made a few stops, after 3 stops I got back to the truck and went to start it, lots of cranking, no starting (or even trying to start, no coughs, no sputters). After about 15min of checking things and trying to start it several times, it finally growled to life. I tried to make a dash home, but about 1/2 mile away, i had to stop for a light, and it died as I Idled to the light. I got it towed home. Today 3 days later, I tried it, and it starts perfectly. I drove it around the yard, and stopped and started it 10-15 times with no problem.

Any ideas? Anywhere to start looking?

Truck info: '99 Disco 2.

Thanks