Sidebr is a greasemonkey userscript that restores the Posts/Followers/Messages/Drafts/Queue sidebar back to the dashboard.
Catching Elephant is a theme by Andy Taylor
I was bored.
(Source: sidebr)
If your Sidebr disappears after updating, try resetting Sidebr (left icon on the controls typically found under the radar).
Added the following:
Q. What are these things on the bottom of my Sidebr?
A: Here’s a picture!

Looks like Tumblr is changing some behind-the-scenes stuff.
Made a quick update to fix the look and feel.
Did something dumb. Fixed it. Here is the temporary stopgap again.
Bug in 3.0 involving tags with editors and contributors (thanks thefrogman). Temporarily (hopefully) removed /tagged from the includes list while I investigate.
Here is the temporary stopgap.
New features:
A quick demo of the new features.
Someone reported that the last update broke Sidebr in Opera. If so, you can use an older version. A little research gives me some idea on why it might’ve broken, but I haven’t started writing a fix.
Stay tuned!