CampTune from Paragon Software Group promises to do one thing and one thing only: resize your Boot Camp partitions without erasing the data on either.  Right now, CampTune is in beta so it is free to brave souls out there.  Paragon will start charging for it once the code leaves pre-release.  CampTune is actually a Linux LiveCD, so you must burn the iso file that you download to a CD and boot off it.  When I tried CampTune on my own computer, it failed to resize my partitions and kicked back an error.  Luckily it did not corrupt anything on my hard drive.  For failing to do the one thing it promised, CampTune will be stuck with the shame of being the first product to be given the Just Plain Tech Seal of Disapproval.  Let us hope Paragon makes their product actually work before they start charging for it.