Though I was pitifully too busy to follow-through on most of my 3W4DW plans, I did manage to make one successful post! Possibly as these kinds of technical things are precisely what's consuming my brain right now. Here is this thing what I built:

Scripty goodness: Fanfiction Header Builder

The Fanfiction Header Builder is a tool made to help you create nicely-formatted headers for your stories with ease.

Just select the elements of the header you want to include, enter your own material, and then copy & paste the code into your "compose entry" text box (in plain text mode, of course).

The (now unlocked) mirrored LJ post can be found here.