I've found this random list of software to be really useful for tasks from working with images to improving Internet Explorer to developing FaceBook applications.
1. IrfanView (www.irfanview.com) - great for basic image editing (resizing, cropping, creating thumbnails, etc.) and screen capturing.
2. WinRAR (www.rarlabs.com) - great for working with zip and other compressed files. Also great for working with CD and DVD image files (e.g. .iso files)
3. Inline Search for Internet Explorer (http://www.download.com/Inline-Search-for-Internet-Explorer/3000-12777_4-10581544.html?tag=lst-1) - provides FireFox style searches for Internet Explorer.
4. Internet Explorer Developer Toolbar (http://www.microsoft.com/downloads/details.aspx?FamilyID=E59C3964-672D-4511-BB3E-2D5E1DB91038&displaylang=en) - useful tool if you develop web pages.Has a host of features to analyze and validate HTML, CSS, and other web site features. Includes a feature to see how your site looks at different screen resolutions.
5. FaceBook Developer Toolkit (http://www.codeplex.com/FacebookToolkit) - allows you to build FaceBook apps within Visual Studio.
6. Microsoft Office Outlook Connector (http://www.microsoft.com/Downloads/details.aspx?FamilyID=7aad7e6a-931e-438a-950c-5e9ea66322d4&displaylang=en) - "With Microsoft Office Outlook Connector, you can use Microsoft Office Outlook 2003 or Microsoft Office Outlook 2007 to access and manage your Microsoft Windows Live Hotmail or Microsoft Office Live Mail accounts, including e-mail messages and contacts."
7. Live Search Maps for Outlook (http://outlook.maps.live.com/minisites/local/outlook/default.aspx) - Allows you to automatically search for location addresses in your events and add maps, driving directions, and estimated travel times to your events. Reminders can be adjusted based on travel times.