Dave,
I have a DCI light. It comes with a UV light, a regular inspection light and a black light. I rarely use it but it has really come in handy a couple times. A few weeks back we had a very bad coffee spill in a very high end commercial job we maintain. The janitors had already tried a couple things on it, I wasn't sure what.
I went in a tried extracting it and nothing touched it. Then I soaked the area with stain magic and put the DCI light on it over night. When I went back the next day the coffee was completely gone. It may have worked without the DCI light but I was convinced it sped up the reaction considerably.
Jeff