[Update at Bottom]
Ok, for those of you that have ever used Linux, then there may be the chance that you might have had to use xkill. But, for those that have never used Linux, then here is a good summary for you...

An App that your using Freezes, and your first thought it to CTRL+ALT+DEL to bring up Task manager, then you have to wade thought the processes to find said frozen app, then kill it... Or you use xKill.

Using a system wide hook in xKill, when it is running, just Press Control+Alt+Backspace, and you will see a Skull and Crossbones follow behind your cursor. When you click on the next item (say, the frozen application), it will kill it. simple.

And just because i know that people will try this out with out having an app to kill, when the skull and crossbones is up, if you choose NOT to kill any thing, press Escape, and you will exit out of xKill mode.

No external references, this app is Portable, you will know when it is running doe to the color changing Skull and Crossbones in your system tray. you can Right click on the glowing icon to either go in to xKill mode, so that you don't have to do Control + Alt + Backspace, or you can exit out of xKill.

[Update]
At a user's request, you can now disable the tray icon... but then you have to use Taskmanager to kill xkill.
Fixed the (C) info also.