Thanatos is the Greek god of Death, and a character in the Piers Anthony series "Incarnations of Immortality". I have been, in the past, a funeral director. I hope that I was a compassionate one (as was the book character).
The "8877" is a play on my service number. Combined, the two make a killer name that has never been "taken" on any other board of any other type. Basically, if you see "thanatos8877" anywhere on the internet, it is almost certainly me.