I work on a stand alone work station on which I'm the only user. I find it infuriating to sometimes have to shut down BOTH ArcMAP & ArcCatalog in order to rename or delete files that have been created as tests - there's a limit to the patience needed to invent new names for test output files when I'm the only one using the program. The rename restriction is a bother when one uses raster calculator without a file name as the test, but produces a useable result called "CalcXX" as the default which sometimes cannot be renamed. (yes, I'm aware that the 'Calculation' entry in the TOC can be saves a permanent, but this needs to done immediately)
This idea has been merged with Manage Schema Locks.