After many occasions of returning to my desk to get a link or a program I needed to work on a user's machine, I've found a much better solution: I put portable applications on a USB thumb drive, then connect my thumb drive to the user's machine and get to work without walking back and forth to my desk.
On my USB drive, I've assembled a nice toolkit of applications that don't require installation on a host machine. I use Mozilla Firefox ? Portable Edition to keep all my links handy. The default settings save everything to the USB drive.
I've installed many freeware and shareware network tools on the thumb drive, including NetCPS, a network performance utility; PCATTCP, a benchmarking tool; ShareWatch, to show me who's connected to a computer and what resources are being used; PingPlotter, a troubleshooting and diagnostic utility; Angry IP Scanner, a network analyzer; NETCAT, a networking utility; IP List, which enumerates network interfaces; and DiamondCS OpenPorts, a port-to-process mapper. I keep all the reference information on my USB drive organized with PStart, a powerful launcher for all of the applications and media I have on the drive. PStart even includes a note section so I can jot things down as needed.
With a little searching, you can find portable applications to do almost anything you need. There are portable versions of many of your favorite applications, with more popping up every day. Check out http://www.portableapps.com for Pstart and Firefox Portable, then head over to http://www.tinyapps.org for some nice network tools.