Looking for useful new Windows utilities for tech support. What do you use?

I have a LOT of Windows utilities of all sorts but my Must Haves are:

http://www.ubcd4win.com/

What is the Ultimate Boot CD for Windows?
UBCD4Win is a bootable CD which contains software that allows you to repair, restore, or diagnose almost any computer problem. Our goal is to be the ultimate free hardware and software diagnostic tool. All software included in UBCD4Win are freeware utilities for Windows®. UBCD4Win is based on Bart's PE©. Bart's PE© builds a Windows® "pre-install" environment CD, basically Windows® booted from CD. We include many free hardware and software diagnostic tools that allow you to fix almost any problem you will face with your computer. With network support, the ability to modify NTFS volumes, recover deleted files, create new NTFS volumes, scan hard drives for viruses, etc. this project includes almost everything you need to repair your system problems. This project has been put together to be the ultimate recovery cd and not a replacement OS (Operating System). Please visit the "List of Tools" page for a complete list of what is included in the latest version of the project.

http://www.ultimatebootcd.com/

You need the Ultimate Boot CD if you want to:

Run floppy-based diagnostic tools from CDROM drives. More and more PCs are shipped without floppy drives these days, and it is such a royal pain when you need to run diagnostic tools on them.

Free yourself from the slow loading speed of the floppy drive. Even if you do have a floppy drive, it is still much much faster to run your diagnostic tools from the CDROM drive, rather than wait for the tool to load from the floppy drive.

Consolidate as many diagnostic tools as possible into one bootable CD. Wouldn't you like to avoid digging into the dusty box to look for the right floppy disk, but simply run them all from a single CD? Then the Ultimate Boot CD is for you!

When you boot up from the CD, a text-based menu will be displayed, and you will be able to select the tool you want to run. The selected tool actually boots off a virtual floppy disk created in memory.



Ultimate Boot CD has tools in the following categories:
Hard Disk Installation, Hard Disk Diagnosis, Hard Disk Device Management, Hard Disk Wiping, Hard Disk Cloning, Hard Disk Sector Editing, Partition Tools, Boot Managers, File Tools, NTFS Tools, System Burn-in Test, CPU Test, Memory Test, Peripherals Test, CPU Information, System Information, Benchmark Applications, BIOS Utilities, DOS Boot Disks, Antivirus Tools, Network Tools.

http://www.nu2.nu/pebuilder/

What is BartPE and PE Builder?

Bart's PE Builder helps you build a "BartPE" (Bart Preinstalled Environment) bootable Windows CD-Rom or DVD from the original Windows XP or Windows Server 2003 installation/setup CD, very suitable for PC maintenance tasks.

It will give you a complete Win32 environment with network support, a graphical user interface (800x600) and FAT/NTFS/CDFS filesystem support. Very handy for burn-in testing systems with no OS, rescuing files to a network share, virus scan and so on.
This will replace any Dos bootdisk in no time!