dotPeek
If you’re a software engineer using .NET languages, you’ll know about Reflector for .NET, a useful tool for examining and decompiling .NET assemblies. Reflector, originally written by Lutz Roeder now distributed by Red Gate Software, has been a staple tool for .NET developers for several years.
Reflector was originally free, but has been steadily commercialized by Red Gate. Now, there is a new kid on the block. JetBrains is trialling dotPeek, currently available through an Earl Access Programme (EAP). According to JetBrains, “The main idea behind dotPeek is to make high-quality decompiling coupled with powerful ReSharper-like navigation and search features available to everyone in the .NET community, free of charge.”
I tried decompiling one of my more complex classes and I’m seriously impressed. If the symbol (.pdb) files are available, it’s able to perfectly reconstruct the original source files, comments-and-all. Check this out:

Nice one, JetBrains!