Windows process manager has become one of the most essential tools enabling you to kill all those processes and running tasks that hang-up your PC. However, the problem is it's way too basic and sometimes ineffective because it simply can't open when you've suffered a particularly bad crash. Bill2's Process Manager gives you far more control over this tool helping you to manage, rule, and memorize the priority of tasks running on your machine. Apart from displaying processes in much cleaner detail, the program makes it possible to create rules to indicate in which priority a program must be carried out, and even which processors it can use. This is excellent if you're running two processors and one is getting constantly overloaded although that probably only applies to a minority of users on very high-spec machines (in which case, crashes caused by running processes will not affect you much anyway).
The interface is Task Manager like, displaying all sort of information about running processes, from ID, CPU usage, task running, priority and core affinity, to full path of the process.
All in all, Bill's Process Manager may come in pretty useful, provided that you want the best performance of the system with the slightest effort from your part. It ensures that, once a certain process enters idle state (or hits user defined CPU values), its priority will be lowered automatically. More than this, in case of multicore CPUs, Bill2's Process Manager can help you decide the affinity of a process.
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Acrobat Distiller 
Adobe Photoshop 
CardScan 
Selfish Net 
iVMS 4200 
uPLAY by Ubisoft 
Hard Time
Guest I still prefer Process Explorer. It shows mini graphs, has an option to find the process related to each window, highlights different types of processes (.NET, packed images, services) and gives more information about each one (such as a description, private bytes and a working set).
Guest very useful
Bill2
All-in-one tool to manage processes