Sorry, but I ain't putting up 30 URL's. I'm far too lazy for that. Just google for the names.
Free stuff:
Digsby - Nice IM. Hooks up to every IM protocol but IRC. It's a memory hog, but the next release addresses this, using half the memory of the original.
Juice - Good podcast receiver, although it hasn't seen a new version in a long time.
FileZilla - Excellent free FTP client. Works seamlessly with Windows explorer, so uploading and downloading is just a drag-n-drop operation.
Notepad++ - Terrific free text editor.
XCalc - RPN calculator. Good for you folks who do RPN. The UI looks like something right outta Windows 95 (and it is), but that's my only complaint.
uTorrent - Small, fast, and excellent bittorrent client. Also notable that it is the only app that updates itself properly.
Gom Player - Very nice general media player thingy. Plays all kinds of media formats. Much lighter on system resources than Windows Media Player. If only it had a mode that ran in the taskbar (ala Windows Media Player), I'd use it for everything.
NSIS - The installer I use for all of my games. Small. Easy. Free.
NSIS Editor - This is rather cheesy and never gets updated, but it works. It's basically Windows Notepad that runs the NSIS compiler and reports errors back to you.
Adobe Reader - You know what this is.
IntelliType and IntelliPoint - These are the programs that come in the CD that comes with Microsoft mice and keyboards. They basically add a couple of tabs to the standard Windows mouse and keyboard control panel, giving you a couple of extra functions like reprogramming all the soft-buttons on the keyboard.
Virtual PC 2007 - Yeah, I know VMWare is better. But I friggin' hate VMWare. First off, the free version is crippled. And it puts tendrils into every Windows subsystem that the uninstaller doesn't remove. I was finding folders of VMWare stuff in my old machine a year after uninstalling it. Virtual PC is fully featured, is free, is comparatively small and unobtrusive, and it does what I need it to do, namely run a couple of legacy OS's for me to test games.
CCleaner - Gets rid of bits of old stuff that your machine doesn't need anymore. One hint is to run the registry-cleaner 2 or 3 times in a row, as it often finds registry bits that previously depended on bits that it deleted in a previous pass. Hasn't yet deleted anything important for me.
AVG Free - Finds viruses. Is free. Duh.
Not Free Stuff:
DeepTrawl - This was a freebie that I got for helping the developer test it. It's a very nice website-crawler that finds all kinds of crap on your website after it's been put up on the server. Dreamweaver's site validation does a good job of finding stuff on your site that's nonstandard or breaks under certain browsers, but DeepTrawl goes even further. Some of its recommendations are a bit persnickety (like demanding that every picture have alt-text), but I'd rather have more information than less.
Network Magic - Makes Windows networking dirt-simple. Puts up network maps. Audits your whole network for software updates. Well worth the price. Only complaint is that the Mac version is a pretty poor cousin of the Windows version.
PowerArchiver - The best ZIP tool. There are some free ones that are pretty close and, to be honest, I'd probably go with one if I didn't have this registered.
MS Office 2007 - I could probably live with OpenOffice if I didn't already own this, so it's tough to say if I'll upgrade to later versions.
Flash CS3 - I have the whole CS3 Suite, but I ended up only installing Flash. The other two Adobe apps I use heavily (Fireworks and Dreamweaver) are now running as the new CS4 betas from labs.adobe.com. I might reinstall Illustrator, as it's a good way to convert PDF content to AutoCAD, which I occasionally need to do.
MS Expression Suite - The only thing in the Expression suite that I really use is Expression Media (formerly iView), which is still the best media browser and cataloger I've found.
Firefox Add-ons
Autofill Forms - Click the little pencil-button and your web-form automatically fills up with your name and address and such. Perfect for a free-sample-junkie like myself.
Better GCal - I use netvibes.com as my homepage, with Google Calendar in a big frame so I can see my daily agenda. This add-on strips out the bits along the top and left of Google Calendar so it works better as a homepage widget.
Better GReader - Same thing, but for google reader.
ChatZilla - As I mentioned earlier, Digsby doesn't support IRC and Trillian's IRC seems to be pretty broken, so I go with Chatzilla for IRC.
Foxmarks - Syncs up my bookmarks between my desktop and laptop. Works wonderfully. Completely invisible.
Searchbar Autosizer - Makes that little google search-field small until you need it.
Google Gears - I've not yet started using Google Docs offline, but this is needed for that.
Stuff that didn't work in 64-bit
AVI.NET - I used this with DVD Decrypter to rip the occasional DVD to an AVI file. Unfortunately, AVI.NET apparently doesn't recognize the XVID or DIVX codecs on 64-bit machines. I liked AVI.NET because it was dirt-simple to use. I guess I'll need to find another solution there.
Archiving 7-zip
I hadn't heard of NSIS, thanks for the links - there's always something you didn't realize existed or would be useful.