I'll often draw while waiting for renders, more fun than watching the progress bar, but I got stuck for a subject, so I drew myself waiting for a render. It's the kind of "real life" moment that makes for Great Art.
Same thing for the post-it note drawing, there. Had a bad headache that day. Al Jaffee's done it better, but did he have a headache at the time? Huh? Possibly. Never met the man.
Also, been on a bit of a Zatanna kick lately. Not sure why, barely know anything about the character. It's probably all the backwards talking, now that's sassy!