So, in my quest to identify ways in which to increase the fun and "value" of PerlMonks, I thought of image macros.

(Background: Here's the wikipedia article on image macros, though I don't think it describes it clearly.)

My proposal is simple:

1. Image macros would be inserted in a post with shortcut-like markup, e.g. [macro://advicedog|use strict and warnings/RTFM] which would result in an image like this.
2. The available images would be strictly controlled by TPTB (gods, maybe pmdev). The ability to upload an image for the purpose, or to link to an off-site image for the purpose, would be explicitly unpossible. Of course, users would be free to suggest new images via PMD, /msg [pmdev], etc.
3. Image macros would only work in posts, not in the cb.
4. There would be a checkbox in one's user settings by which the fuddy-duds could turn off the funk. For them, the above could be rendered as advicedog says: use strict and warnings/RTFM maybe. (I know this example is lame. This kind of cleverness is not my strong suit.)
5. We could make it so that it would only work if the author of the post was at least a certain level. I'm thinking something relatively low, since the potential for abuse is so small. How about Level 6: Scribe, which currently has no other special powers/privileges?

Update: Additional ideas courtesy of kcott, below.

6. The images — which would be hosted here on-site, probably — would be limited in size to something reasonable. (200x200?)
7. You would only be able to insert one per node.
8. The macro would be rendered with appropriate markup for styling, e.g. <span class="imagemacro advicedog" ... This would enable you to, for example, hide macros altogether, if even the non-image rendering (see #4 above) is too much for you.

By the way — even if this feature does get approved for the pmdev to-do list, its priority is likely to be pretty low. There are too many other enhancements of much greater impact and benefit to be done yet.