I have a C++ Application, when I observe Task Manager, it shows that applicaiton\'s memory usage increases gradually.
I manually check my source code, and I used Vis
I use Extended Task manager http://www.warecase.com/products.asp
This is useful for debugging purpose especially to check if a thread exists or not and other such cases. It can provide lots of information if you have pdb for your process or application.
Probably you can use DevPartner for identifying memory leaks. It is very useful.