From the "What could possibly go wrong?" department: starting a WPF application (verified offenders are MsbuildG and VistaBridge from the Windows Vista SDK) crashes Vista. Or the graphics driver to be more precise. The result is nonetheless a perfectly reproducible BSOD on my IBM X31 laptop. The funny part? This ATI Mobility driver (6.14.10.6546) came from the Windows Vista Update Service and is MS HW Compat signed!