sysinternals was already mentioned, but I wanted to point out Desktops explicitly. It's an awesome tool when it works.
Desktops allows you to organize your
applications on up to four virtual
desktops. Read email on one, browse
the web on the second, and do work in
your productivity software on the
third, without the clutter of the
windows you’re not using. After you
configure hotkeys for switching
desktops, you can create and switch
desktops either by clicking on the
tray icon to open a desktop preview
and switching window, or by using the
Right now I have a 16GB OCZ Rally2 which I find dead handy. I keep lots of the tools mentioned above on it (in portable app form, mostly).
I've got the contents of some useful OSs on there: notably Windows XP, Server 2003, and also the Win 7 Beta. I created a partition that is compatible with W7 too so I can install directly without an optical disc. Dead handy for testing on laptops with varied hardware configurations.
Just wondering... How big is that flash disk supposed to be? I myself have one that is 32 GB and there's a lot that you can fit on that. ;-)
If you use it on a system that can boot from USB, you might even consider installing a complete operating system on it, to run from USB. (Most likely going to be Linux.)
I'm a fan of SIW (System Information for Windows). Lets you check a lot of computer information from a small exe file that fits on a thumb drive. It's got a free version as well which has always done everything I needed it to.
Windows NT 3.5 File Manager (winfile.exe). A single file that gives me raw access to the file system. For 2000/XP use the version that came with NT4 Service 4. Under Vista/7 the original version doesn't run anymore, but there is a patched version at
4NT, a powerful command line interpreter, for the cases when Powershell is not installed.
Sadly, the vendor discontinued it.