I think its Mcafee that has a little AV prog called stinger that works pretty well.
Sysinternals has process explorer and tcp view that are helpful.
PExplorer is a much better task manager and TCP view is very helpful with network connections.
Barts PE is a downloadable disk that has several different utilities that are helpful when needed.
Sisoft Sandra is a great prog that has served me well. I dont know if you have ever heard of it but it is a system info prog. that gives very detailed info, testing, and benchmarking options.
Another thing that I try to include on my resource disk is a text directory that I keep notes about everything from changing locations of MYDOCS to MS KB articles on how to accomplish different steps.
Also in that I try to keep links to different sites that I find helpful for things like stop error codes and troubl shooting steps.
Im currently in the process of moving those types of files and favs. links to a thumb drive because they change often and I can also add new things to it at the customers place if needed. This way I dont have to write a new disk all of the time as things change.
I am going to still keep the links stored in text format on the disk just in case they have USB problems, but keeping the list up to date on a disk is a pain.
I have some others but the disk isnt here so when I see it Ill try to add to this list.