Space eaten by VS2005 SP1 orphaned installer files

When trying to install VS2008 on my work desktop, I noticed that actually I have no space on drive C: where VS 2005 is installed.
Running the following directory/files statistics program (which I found over time to be the best of its kind): http://windirstat.info/
I found out that the 39GB space was eaten by the files of the 441.5 MB size, further investigations showed that those were VS2005 SP1 installer orphans. Following blog describes the problem and the solution to it:
http://blogs.msdn.com/heaths/archive/2007/01/31/how-to-safely-delete-orphaned-patches.aspx