For a long time, one of the huge advantages of using Java over .NET has been that the Java library source code has been freely available - and browsing through it is very helpful for understanding library behaviour and for debugging.
Now, finally, the .NET Framework source code is also (mostly) available. Unfortunately, it’s in a slightly inconvenient form - it’s downloaded on demand as you debug into classes in VS.NET. So, some enterprising developers have written the NetMassDownloader which lets you download all of it at once, for offline reading, and general browsing. This is immensely useful! Thank you Kerem Kusmezer and John Robbins!