Its always nice as a developer when you find a new tool to make your life easier - understanding what is actually happening during the execution of your application (rather than what you think is happening) is key to fixing those hard to find bugs.

Visual Studio does a pretty good job of helping with this with its condition break points, break on thrown exceptions etc however its not always quite enough, I normally have a whole series of other tools open when debugging an application - whether its one of the sysinternals tools (dbgview, filemon, regmon, handle, and pstools among others), a copy of Ants Profiler or the SQL Server Profiler.

So its always nice when you find a new tool which makes your life even easier - I came across the managed stack explorer the other day which seems to be a great way to log how your stack changes over time - I'm not sure they have the architecture totally correct as it polls the application every x milliseconds rather than giving your a trace - personally I would rather have a trace of the stack over a period of time with the ability to explore the arguments of each call without having to step through the applicaiton - but it is certainly an interesting and potentially useful tool.