I saw one on reddit a couple days ago. The guy had been doing it about a week or so. It wasn't even a good comic.
I don't really get it. No one is going to give you money for a comic that is a week old, a month old, or even a year old. It takes time to develop a following to where you should be getting money. I wouldn't even consider it until my comic is 2 years old or I'm getting 5000 hits a week (on my site, not here).