This is the best news I have ever heard! I wonder why they opted to commercialise it in the first place when there are so many open source alternatives.

No more mocking about with Arduino!!!!!!!!

Now I can look around my old electronics for the latest candidate for iRobot!

uuuuuuurbyyyyy. JBosses (Java bois)

Pharoh:

http://www.betanews.com/article/Microsofts-NET-Micro-Framework-is-now-free-and-open-source/1259001513

Very interesting, I must confess I am slightly suprised, but I noticed that its not 100% open-source:  "Microsoft pulled the framework's cryptography libraries and also stripped out its TCP/IP stack because it contains third-party software licensed from EBSnet, wrote Galli."  But its a move in the right direction, the future looks open!

transformR:

Very interesting, I must confess I am slightly suprised, but I noticed that its not 100% open-source:  "Microsoft pulled the framework's cryptography libraries and also stripped out its TCP/IP stack because it contains third-party software licensed from EBSnet, wrote Galli."  But its a move in the right direction, the future looks open!

I think you can get open source versions of those libraries as separate downloads (not 100% certain), but I recall that when I downloaded the source code there where suggestions for separate downloads of a tcp/ip stack etc.
The framework itself is under the Apache license.