PowerToys is a bunch of great utilities for Windows XP users. Most of them are easy to use. I especially like SyncToy which will help you back up your important files and the Image Resizer which lets you quickly and easily resize several photos at once.

The only caveat is that there is no Microsoft support for the PowerToys. However, I've been using them for years without any problems. Here is the list of the current PowerToys directly from Microsoft. Each has a quick explanation of what they do. You can download each PowerToy separately at the  Microsoft website.

Image Resizer

This PowerToy enables you to resize one or many image files with a right-click.

SyncToy

With new sources of files coming from every direction (such as digital cameras, e-mail, cell phones, portable media players, camcorders, PDAs, and laptops), SyncToy can help you copy, move, and synchronize different directories.

Color Control Panel Applet

Professional-level photographers and designers know that getting consistent, accurate color from file to screen to print and beyond is a requirement for great results. This new tool helps you manage Windows color settings in one place.

RAW Image Thumbnailer and Viewer

Are you a serious photographer? Now you can organize and work with digital RAW files in Windows Explorer (much as you can with JPEG images). This tool provides thumbnails, previews, printing, and metadata display for RAW images.

ClearType Tuner
This PowerToy lets you use ClearType technology to make it easier to read text on your screen, and installs in the Control Panel for easy access.

HTML Slide Show Wizard
This wizard helps you create an HTML slide show of your digital pictures, ready to place on your Web site.

This PowerToy adds an "Open Command Window Here" context menu option on file system folders, giving you a quick way to open a command window (cmd.exe) pointing at the selected folder.

Alt-Tab Replacement
With this PowerToy, in addition to seeing the icon of the application window you are switching to, you will also see a preview of the page. This helps particularly when multiple sessions of an application are open.

Tweak UI
This PowerToy gives you access to system settings that are not exposed in the Windows XP default user interface, including mouse settings, Explorer settings, taskbar settings, and more.Version 2.10 requires Windows XP Service Pack 1 or Windows Server 2003.

Power Calculator
With this PowerToy you can graph and evaluate functions as well as perform many different types of conversions.

CD Slide Show Generator
With this PowerToy you can view images burned to a CD as a slide show. The Generator works downlevel on Windows 9x machines as well.

Virtual Desktop Manager
Manage up to four desktops from the Windows taskbar with this PowerToy.

Taskbar Magnifier
Use this PowerToy to magnify part of the screen from the taskbar.

Webcam Timershot
This PowerToy lets you take pictures at specified time intervals from a Webcam connected to your computer and save them to a location that you designate.

You can download any or all of these PowerToys at the Microsoft website.