I thought of sharing few of the best FREE software that I have used. May be it would help few of you guys too..
Paint.NET is free image and photo editing software for computers that run Windows. It features an intuitive and innovative user interface with support for layers, unlimited undo, special effects, and a wide variety of useful and powerful tools. An active and growing online community provides friendly help, tutorials, and plugins.
2. WorldWide Telescope
WorldWide Telescope (WWT) enables your computer to function as a virtual telescope, bringing together imagery from the best ground and space-based telescopes in the world. Experience narrated guided tours from astronomers and educators featuring interesting places in the sky.
3. Visual Web Developer 2008 Express Edition
Visual Web Developer is a tool for creating and working with web sites in a variety of configurations. An easy solution for creating webpages.
4. Circle Dock
Who says a dock has to actually... dock? To the side of the screen, that is. Circle Dock brings up a spiraling launcher interface with all the icons you want to click. Rotate it with the wheel on your mouse and change the skin to suit your desktop.
Replace the Windows Taskbar and Quick Launch toolbar with this Mac-like animated toolbar of icons for all your programs. It comes with a few "docklets" for displaying info like the time, weather, and a Web search form.
On a par with any commercial audio editor, Audacity is the free sound editor of choice. The latest beta (1.3.6) even supports MPEG-4, Dolby Digital, and Windows Media.
Do I have to explain iTunes as the (so far) ultimate media player, coupled with online store and the primary way to get media—from music to video to games to podcasts, which plays most file formats (except, unsurprisingly, Windows Media formats)—and puts them on your iPod or iPhone.
8. MozyHome Free
Don't even think about backing up: MozyHome will do it for you, in the background, for up to 2GB of data (you can pay to get unlimited space). Perfect for office docs, but you'll want to pay for more storage to back up pictures, music, or videos. Soon it will sync between PCs, too.
Fast page load times are a hallmark of this browser, the default for Mac and also available for Windows now. Safari offers private browsing which is a cool feature. And one of the best web browser that I have used.
Still the best—and smallest—BitTorrent client in existence, uTorrent will have you downloading big files in no time. Very fast and consumes less memory footprint compared to other torrent clients.