After a call to Graphics.DrawImage, an OutOfMemory error might occur.  The 
probability of an error has some correlation with the size of the image but 
is not reliable.  Even with an image of a few hundred megabytes, sometimes 
the error occurs and sometimes not.  Some random postings on the web and 
newsgroups say the image file is broken, well, the image file doesn't 
alternate between being broken and not.  The error is intermittent.

When running under a debugger, sometimes Visual Studio asserts that the 
error occured in some other random place such as Application.Run.  But not 
always.  So I think sometimes the stack is getting smashed.

Now get this.  Inserting some calls to GC.Collect *increases* the 
probability of an OutOfMemory error.  Deleting those calls *decreases* the 
probability.  This seems backwards, right?  Well, not if the errors are due 
to one particular kind of bug.

I think Graphics.DrawImage is forgetting to pin a pointer before calling a 
Win32 API.  I think the garbage collector is collecting stuff that the Win32 
API thought it was going to use.