GTK Spinners leak memory when spinning and visible. If you hide the widget, or
stop it spinning, the memory usage does not go up, but it does not reset
either. Memory usage will continue to climb once you start it visibly spinning
again. It also leaks when behind another window (for instance a terminal).

Minimalistic example:
--
import gtk
window = gtk.Window()
spinner = gtk.Spinner()
window.add(spinner)
spinner.start()
window.show_all()
gtk.main()
--

Run the example and watch the python process memory usage climb up by a few Kb
per second. It isn't a very quick leak, but anything that relies on GTK
Spinners will crash after several days once the memory usage gets too high. One
example (of many) is Glade, with a visible spinner, left open over a weekend,
will result in a crash by the time you come in on Monday morning. 

This bug makes it difficult to have long running, robust programs.

This bug is a copy of the bug #683246, however I believe it affects not only pygtk. Can anyone test that properly?