I came upon this one by accident yesterday while hunting for other things... I have to give credit to the author of this one because it's so deviously simple, dangerous, exciting, and potentially useful -- just like me.
What it does
: Enables 'grayed out' windows controls like checkboxes, radio buttons, and menu items in many applications.
Why it's useful
: Think about how many times you've wanted to click something only to see that it's disabled. True, oftentimes there's a good reason for that, but you'll never know otherwise. It's your computer, you do what you want.
As the website says, "you’d be surprised at how often it comes in handy."
Why it's dangerous
: Now you're bound to second-guess every safeguard encoded into the apps on your PC. Careful with that curiosity, meow-meow.
How to use it
: Run the .exe. That will put an icon in your system tray. Single-click the icon. That will turn on the enabler. Now just click a normally disabled control in some other application to enable it. When you're done enabling things, single click the system tray icon to turn it back off. Right-click and select Quit to remove the icon.