Balsamiq - Balsamiq. Rapid, effective and fun wireframing software.
ANTS Performance Profiler - Speed up the performance of your application with ANTS Performance Profiler, for .NET code analysis.
Invision - Prototyping and collaboration for design teams
Deleaker - Deleaker finds memory leaks, GDI leaks, leaks of handles, USER objects and others. Available both as a Visual C++ extension and standalone application.
Zeplin - Collaboration app for UI designers & frontend developers
Relyze WonderLeak - WonderLeak is a native Windows allocation profiler, designed from the ground up to be blazingly fast and handle profiling large multi threaded applications with ease.