DigitalRev is known for doing some pretty interesting things on their YouTube channel. In one of their latest episodes they tasked a professional photographer with building a DIY ring light to use on a model who would be showing up in 2 hours.
Amazingly the design that he came up with is actually pretty perfect, and while not ideal for all situations, it works pretty well for a DIY light build. Basically they destroyed a fan, some bathroom lights and built a DIY power-box to power the thing. Then they added a mount making it compatible with a lightstand or tripod. Check out the video below, its a pretty neat setup honestly.