The ultimate boot cd is nice, so is Knoppix for those pc's that wont boot into the installed OS. I also carry a couple of free spyware/virus/trojan detection/cleaning programs and a few paid ones. Radmin is a nice little app to drop on a pc if you know you will be supporting it more then once and want to do it from another location in windows. I like CPU-Z and Sandra for system info. So much of this is system specific. Patchs, drivers, updates, and things like that are all specific to what your supporting. I'll be damned if I'm going to keep current cd's with patches for all the operating systems out there.
