I have found an issue with Parallels when my EyeTV Hybrid is plugged in. The EyeTV seems to install a driver that is incompatible with Parallels. When I try to start Parallels, at first I get the message "Unable to allocate memory for moniter PE!" If I am persistent, the whole iMac crashes. At least Leopard has an entertaining blue screen of death. Your screen turns a transparent blue in a wipe from top to bottom, and it tells you that you must restart your system immediately. If I totally quit EyeTV, and reboot with no autostart options in EyeTV, I can run Parallels, so this is a workaround. I am running a new iMac 24", 2.8 mhz, 2GB, 500GB, OSX 10.5, Parallels 5540 Beta, Windows XP.