Each time I run a test in nunit I get another nunit-agent, which does not exit the test completes, or when the tests are reloaded in nunit or when I restart nunit. 
 This ever increasing list of nunit-agent.exe's creates a increasing problem when I try to attach to process from VS2010 and try to debug the running test 

Any ideas, 
 Trying to task kill these process is not the answer ....
(my environment VS2010, dot net 4.0, nunit 2.5.8, ... )