Jtoxification's Journal: Most useful tools in Windows (*nix has everything already)

Textpad:
Text editing, with custom syntax highlighting, tool/program/batch file/macro adding and calling, color-highlighted code2html, caps-formatting, sort, tables, join lines, regular expression searching across single and multiple files, clipboard-viewer, and more ...

Aida32: A better msinfo32
... and even has memory read/write benchmarking, report-making in various formats, including html, and every piece of info you would want to know about your computer.

Process Explorer:A far better task manager-
it shows all processes, handles, files, and resources, ordered in tree-view by which programs/processes opened them, and it's recursive in that you can go up a level until you see all open processes at once, which can be sorted to taste. The best part is that you can destroy any open handle ... no more "the file is currently in use" BS.

Cacheman:
The BEST free system tweaker out there. The newest version has more features than 5.11, but has donation-wared their setup-help wizards; 5.11 still has the wizards to help you set up if you're new to cacheman -- otherwise, if you have no use for setup wizards, get the latest version.

Spybot: Search & Destroy:
It finds and destroys all spyware. It is the best. It does what it was created to do. You can't do better than that. :-)

Analog X's Pcalc: The Programmer's Calculator.
This thing rocks. It's a window that takes C/C++ style mathematics (including bitwise arithmetic as well as functions defined in math.h), evaluates them, and prints them in all the formats programmers are used to viewing them (float,hex,octal,integer,binary,char...)!

Regex Coach:
The interactive regular expression evaluator. Having trouble with a particularly tricky regular expression search/find/edit/replace ? This is by-and-large, one of the most useful tools in viewing the results (intended and unintended) of your most intricate expressions in realtime, saving you a lot of headaches!

There are, of course more ... but this is a post about links to (in my opinion) the most useful utilities. (They only had a Utilities journal topic for Apple, so I figured OS-X is good to go already, especially since I've only been able to use it on the Demo G5 station at my school's bookstore, and you can get all the best utilities you need from *nix/*BSD already when configuring your installation, so they need not even be mentioned :-) but that might make for a good "part 2" I suppose ... especially since I'm certainly not done (feel free to add your own best utilities )... I didn't talk about other tweaks like file searchers, encryption & security, etc, or defragmenting, not even compiling (Although I will mention Blooshed's Dev-C++ 5.0 compiler for now, but it uses a windows port of gcc 3.2, anyway :-D , going back to the whole *nix thing.)