TODAY'S NEWS: If interviewers stopped asking writers, cartoonists and artists where they get their ideas, that would be fine by me. I know it seems like a good interview question, but it's really not. Sure, we can go on about creative influences, amalgam and synthesis from other works or inspirational sources, but there are really only two answers, and the best one is: We just make stuff up. The source is our own heads. Sometimes it's when we're sitting at the computer trying to come up with ideas, but often it just happens when we're thinking about other things. When I was considering what present to give to my older brother and his fiancée for their wedding, it occurred to me to just give them toast, which became Comic #669. The whole idea for the Ask Dr. Eldritch advice column came to me when I was annoyed at movie characters who did stupid things, and realized that they needed someone to tell them how to handle the situations they were in. So, in short, we just think things up.
The other answer is "We steal them from other writers," which is honest, but it kinda sounds bad. You can see why we wouldn't want to talk about that.