API Monitor - API Monitor is a software that monitors and displays API calls made by applications and services. Its a powerful tool for seeing how Windows and other applications work or tracking down problems that you have in your own applications

perf - Perf is a simple app monitoring solution paired with meaningful alerts.

Deviare API Hook - Deviare is a professional open source hooking engine for instrumenting arbitrary Win32 functions, COM objects, and functions which symbols are located in program databases (PDBs).

Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.

Microsoft Research Detours - Detours is a software package for re-routing Win32 APIs underneath applications.

Loado - Loado is an easy-to-use monitoring tool for websites that helps developers, products, and marketers to improve user conversions and optimize SEO strategies.