Suffering from ditched system tray support in 13.04. :( Is it technically possible to create universal appindicator wrapper for arbitrary application which supports only system tray icon? Maybe there are already existing infamous projects?
There is no universal wrapper (not that I've found), but the best thing (that I did find) is copy and learn...
1) Some documentation.
2) Many indicators with their source from which to choose and model.
3) My own indicators are a good starting point ;-)