We use a very similar product at work called TreeSize Professional. It gives you the same type of graphical representation of your file system, with larger files shown as proportionally larger boxes. It's very handy for maintaining multi-terabyte user volumes. When you've got 5,000+ user directories on a file share, it can make it much easier to determine who and what is taking up all your space.
Most of the nifty programs that I use are undoubtedly familar to all of you, e.g. IrfanView and CPUID CPU-Z. Here are a couple you might not know about:
PS3 Media ServerPS3 Media Server is exactly what is sounds like, a media transcoder for the PS3. I've dorked around with XBMC, Windows Media Player, and Windows Media Center in the past and found them unable to play a huge swathe of my media. PS3 Media Player can play transcode just about anything I throw at it and deliver it seamlessly to the PS3 to watch on our TV in the living room. Unfortunately, it can't quite keep up with 1080p videos, but anything 720p or less is golden.
NVidia GeForce ExperienceThis is also a freebie, but obviously only applies if you are running an NVidia graphics card. It automatically detects the games you've got installed (and any you install later) and recommends the optimal graphics configuration based on your graphics card, CPU, RAM, and monitors. The optimal configuration for some titles can be really surprising at times. You can also click on each setting individually and see a screenshot that points out exactly how that setting impacts the game. GeForce Experience can also automatically download drivers as they are released and notify you when they're ready to install. If you're obsessed with running updated code like I am, it's a really handy tool.
KeePassKePass is one of many password locker applications, but it's my personal favorite. It uses 256-bit AES encryption to secure your most vital information. Admittedly, I was a slacker for a number of years and only used a handful of passwords for all of my myriad accounts. With KeePass, I finally got around to changing that and I now use a unique password for absolutely everything. Best of all, they are all randomly generated, so I have absolutely no clue what my passwords are. I couldn't be forced at gunpoint to divulge any of them because I don't know what they are. This also allows me to choose ridiculously strong passwords that I'd have no hope of remembering.
Obviously, it's important to make sure you have a damn good backup of your KeePass library and it is vital that you choose the best password you can come up with to secure it. It supports third-party addons, and I used a FireFox plugin that let me extract all of the saved passwords from my browser. That populated 99% of the passwords I use and also gave me a great reference as to which passwords I needed to change. You'll be really surprised at just how many accounts you have out there!
-b0b
(...has more... later!)