Here are some of my favorite generators. I use them for minor characters, creatures, races, and more. The things they generate range from useful to the entertaining, from serious to hilarious.
A character description generator. Great for fleshing out a story with minor characters.
I use it when I need to find the perfect word that rhymes with something else.
This site has a generator for pretty much anything (martial arts moves, organization names, superpowers, technology, magic/spells, creatures, races, etc...)
A random story idea generator. Helpful for getting the creative juices flowing.