Killer Apps - I find useful (all free!)
"An application that proves the usefulness of the underlying technologies".
Defined by Jawed Karem in the speech "YouTube: From Concept to Hyper-growth" held at University of Illinois at Urbana-Champaign ACM Conference, Oct 21, 2006.
www.youtube.com/watch?v=nssfmTo7SZg
In no particular order...
DVD Flick
A super easy tool for creating workable DVDs, complete with options to make menus and titles.
http://www.dvdflick.net/
GIMP 2
Image editor that can do everything. Lots of tutorials around to help one learn it.
http://www.gimp.org/
µTorrent
Lightweight torrent program. Was using Azureus before it went all crazy bloated with Vuze.
http://www.utorrent.com/
XnView
Nice little, fast program that can handle all digital image viewing (400 types of files). Has other options too like cropping, resizing & redeye reduction. Excellent layout, handles like explorer as tree branches.
Winamp Lite
Is 3mb and handles all my music needs (which isn't much, a few thousand songs on shuffle). You need to scroll down the page to find the lite version of the player.
http://www.winamp.com/media-player
Abyss Web Server
I needed a localhost server to test out my sites on. First I tried Apache, then Apache XAMPP Friends but both were too big for my small-time needs. Then stumbled across the Abyss. Super easy to setup and now handles all my localhosting needs.
http://www.aprelium.com/