Primstar is a project that's rapidly approaching a stable 1.0.0 release after 2 years of development. It's a set of scripts that add comprehensive support to Blender for Second Life sculpties.
http://dominodesigns.info/project/primstar
It's a little unusual in using tkinter to provide modal pop-up dialogs and this has provided a few challenges in getting it working correctly cross platform. Currently it's working smoothly on Windows XP, Windows Vista and GNU Linux systems, but there's reports of problems on Mac.
http://dominodesigns.info/node/157
Unfortunately my main Mac tester is in a completely different timezone and exchanging messages once per day isn't a great way to get to the bottom of the problems.
I could really do with some more Mac users to test and confirm whether the problems (Blender not getting focus back, crashing on minimise) are on all Macs or just affect some systems.
Also if there's any developers familiar with Blender and tkinter events who are willing to spend a little time helping to get to the bottom of these issues, that would be a great help in getting Primstar to a 1.0.0 release.
You can download the scripts from
http://dominodesigns.info/node/4/release or checkout with git clone
http://dominodesigns.info/git/primstar.git
All help is much appreciated.