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Erik Robertson O did a quick check. We can use one of open source tree libraries for  Java and then its just using that & building around that. Will sit to it over next few weeks and mock something up.

Erik Robertson how hard do you think it would be to build app like that from ground up as open source? I have some C++/Python experience I would be happy to chip in!

Ok who ever interested in doing open source project like tabs drop me an mail dariusz at dariuszmakowksi com.