
You can download the script here: http://aescripts.com/tag/bg-renderer/
Note: Script requires After Effects 7.0 or higher
This script takes whatever items are queued and ready to render in the render queue and sends them to render in the background using aerender in a new Terminal (mac) or Command (pc) window where the render progress can be monitored.
It also had the added advanced feature to launch more than 1 instance at a time. If you have a multi-processor machine, you can launch as many instances as you have cpu's. In my testing, this cut render times in half on a Quad G5 using 4 intances. (having at least 1 GB of ram per instance launched is recommended).
There's lots of error checking behind the scenes so I did some beta testing to make sure it doesn't have any bugs, but as always please share anything (good or bad) that you encounter.
The script has lots of built in help to clear things up.
Enjoy!
-Lloyd