Of interactive applications, and excluding any special-purpose apps I use for work whose names won't ring any bells:
1. FireFox
2. TextPad
3. TotalCommander (I have a regular love affair with this one!)
4. TheBat!
5. KeyNote
Honorary mentions: locate32, Reget Deluxe, Archivarius (I couldn't see why one would buy a desktop search app with so many available for free, then I realized Archivarius supports TheBat and Forte Agent databases. A lifesaver.)
But then there are non-interactive tools that run constantly in the background and make the whole environment livable. I tend to forget about those until it's reinstall time ev ery few years and I find some things are missing. Here's to those silent, trusty utilities!
1. KatMouse (the functionality used to be present in Logitech drivers, then they removed it)
2. HoeKey (I replaced it with AutoHotkey only recently, but HoeKey served me well for a very long time)
3. FileEx (never want to see the unenhanced File Open dialog again!)
4. Backup4All
5. URLInject (a program I wrote to insert page URL, title and date/time in every html file saved from a browser)
Honorary mentions, I guess: svchost.exe, winlogon.exe, csrss.exe, spoolsv.exe, System Idle Process