The only thing my new user script does is what I felt was the most important function of the old one: it adds a new tab to the answer list that can be used to sort answers by length of the first code block:
It does not include any of the other fancy features of the old user script, but I think it's a lot better than nothing.
The user script has been tested in Mozilla Firefox and Google Chrome. To install it, first download and install the GreaseMonkey (for Firefox) or TamperMonkey (for Chrome) extension, and then click the "install / download" button below:
The script may also work in other browsers with compatible user script support, such as Safari or Opera. See here for instructions on installing user scripts on different browsers.
Edit: Since version 0.3, the script should also work if installed directly as a Chrome extension using the alternative instructions above.
Edit 2: ...and v0.4 should solve issues with direct links to answers. (Previously, re-sorting the answers could leave a completely different answer in view than the one you wanted; now, the view should automatically jump back to the target answer.)
Ps. Shameless plug: if you like this user script, you may also want to try the Stack Overflow Unofficial Patch, another user script I've written to fix various neglected bugs and inconveniences in the Stack Exchange user interface.