Running a Windows Machine in Virtual Box Seamless mode on top of a Kubuntu, can look pretty confusing. I mean, Windows security center right next to KPackagekit and Dolphin?
Anyhow, one of the few reasons I sometimes need to revert to Windows is to run either CA Erwin of Sybase PowerDesigner. It just seems to be the case that there aren't any fully featured data modelling tools for Linux available.
And of course. KFF needs to be tested on Windows. It seems there are people using kettle on windows.