I have used Conjure Candlelight to surprisingly good effect several times.
The first time we had caught a few enemy theurogists skulking about our camp the night before a big battle. One died from a stealth attack, but he other and his guards went to jump on their horses, so my character Balthius cast it under their horses. This spooked them into running away. Unfortunately one of the guards got a good handle animal and manage to keep one of the horses from bolting. He put the therurogist on it, who promptly escaped, and we only got to kill a few guards.
Another time we where ambushing an enemy supply caravan. Our Elementalist had placed a lovely wall of fire right down the center of the wagon train, causing much panic an confusion. Some of the caravan guards started to rally, which was a problem because despite the ones who burned, ran away, or where crushed by the horses and wagons running wild, we where still outnumbered. Balthius cast it around them, and in the smoke and confusion, the extra bit of fire was apparently too much, as they ran in terror too.