4. Microsoft Standalone System Sweeper Tool
Not so hidden, but a nice little gem nonetheless.In case of a (deep) infection of boot files by viruses or rootkits, there's not much a real-time scanner can do. In that case, MSSSST (yes, that's Microsoft's naming convention at its best) creates a bootable CD, DVD or USB key that hosts an offline copy of Microsoft Security Essentials -– including all the latest signatures downloaded from MS servers beforehand.
5. NoReplyAll add-in for Outlook 2007 and 2010
A nice little Outlook addition for sending e-mails in house: "NoReplyAll" (a Microsoft Research Project) prevents e-mail recipients from forwarding or using "Reply All" to spread your e-mail to other co-workers. You can even prevent the recipient from replying entirely. It only works on machines that share the same Exchange server, but it's still a pretty useful addition to your daily Outlook routine.
6. VMMap – A peek inside your PC's memory
Ever wondered how much address space, main memory and virtual memory a running process is using? VMMap has answers -– and lots and lots more. As one of my favorite Sysinternals Suite (see WSCC above), VMMap shows a graphical representation of the entire memory usage that helps you understand the memory cost of every single application you're running or developing. The lower block of VMMap also details which files are being used by the process and how much memory is taken up in the process.