screenshot (t.a.g.)

You've enjoyed the list of all the posts that featured a real screenshot.

They usually introduce a new feature in my tools or a significant visual progress in games. Not all of these are pictures taken with a real camera (hopefully), and they are conveniently complemented by videos (mostly screencasts) for more dynamic features.
In contrast, mock ups are made-up pictures (typically featuring Gimp) for things that do not exist yet out of my personnal virtual world (running Mind OS :)