Silverlight memory leaks finding
Quick post to not forget :)
Article (mentions x86 WinDbg installation under x64 OS): http://dotnetspeak.com/index.php/2010/09/using-windbg-to-find-memory-leaks-in-silverlight-applications/
Also quick cheatsheet:
.load C:\Program Files (x86)\Microsoft Silverlight\4.0.60129.0\sos.dll
!dumpheap -stat
!dumpheap -MT <mt>
!gcroot <addr>