Not necessarily Linux related, but I just got off the phone with a certain large computer manufacture trying to resolve a failed harddisk on a 3 month old computer, and they claim that installing an alternate OS has voided the warranty. In this case the computer shipped with Win7 and the "alternate OS" was XP, but I find the claim ludicrous as I install Linux on all sorts of PC's and the warranty callcenter has never skipped a beat as long as I can demonstrate the fault in an obvious way. This particular computer is a different brand though...