I can't remember where I first learned about this but I was cleaning the glass on my wood stove door today and realized there are probably more than a few people on here who burn wood. Try wetting an old rag, news paper or paper towel, dipping it in the wood ash and cleaning the glass with it. Most of the creosote wipes off with little effort.
We didn't have a fancy stove with a glass door growing up, so I never gave much thought to cleaning one. I moved into a house that had one a few years back though and tried removing the creosote with Windex and various other cleaners and finally settled on a copper scrubber. None of them work nearly as well as water and ash.