Windows 7 Tip: 
Here are the List of 10 Most Useful windows app which are free to Download and very useful for you.
Here is the List.
1) Windows Desktop Search 3.01 for Windows XP (KB917013)
Brief Description: Windows Desktop Search 3.01 is an updated component of Windows that enables instant search on your computer.
2. Microsoft Windows Theme Nunavut
Brief Description: Customize your desktop with Microsoft Windows Theme Nunavut.
3. Microsoft Egypt Nile Theme
Brief Description: An Egypt Nile desktop theme with new wallpaper, animated cursors, new icons, new 4
4. Autoplay Repair Wizard
Brief Description
The Microsoft AutoPlay Repair Wizard scans your computer devices to find defective AutoPlay settings, and attempts to fix those it finds.
5. 3-D American Flag Screen Saver
Brief Description: Reflect your patriotic spirit with this American Flag screen saver.
6. SyncToy v1.4
Brief Description: SyncToy helps you copy, move, rename, and delete files between folders and computers quickly and easily.
7. Windows XP Winter Fun Screensavers
Brief Description: Download these cool screen savers with vivid 3-D and interactive sound effects.
8. Plus! Dancer LE
Brief Description: Experience music in a whole new way with lifelike 3-D and animated dancers that groove on your desktop with dozens of entertaining and hilarious dance moves.
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9. NZ Bliss Desktop Backgrounds for Windows
Brief Description: Free uniquely New Zealand desktop backgrounds & wallpaper.
10. Internet Explorer Developer Toolbar
Brief Description: The Microsoft Internet Explorer Developer Toolbar provides a variety of tools for quickly creating, understanding, and troubleshooting Web pages.
I use Synctoy to sync my thumb drive with my PC. Looks pretty useful so far.