It's been a few times my VS2005 locks up tight for no reason. At first, I thought it only occurred during ASP.NET debugging, but apparently not as it hung while being idle in a standard C# solution. It seems like it hangs occasionally after attempting to update its cache.
Here's the call stack I could retrieve before everything froze:
> mscorlib.dll!System.Threading.Monitor.Wait(object obj, int millisecondsTimeout, bool exitContext) + 0x14 bytes
JetBrains.ReSharper.Psi.dll!JetBrains.ReSharper.Psi.Impl.Caches2.CacheUpdateThread.Run() + 0x90 bytes
mscorlib.dll!System.Threading.ThreadHelper.ThreadStart_Context(object state) + 0x3b bytes
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state) + 0x81 bytes
mscorlib.dll!System.Threading.ThreadHelper.ThreadStart() + 0x40 bytes