The more we go wireless, the more we need wires to charge all those gadgets. It is really a drawback. Let's say I'd wanted to put a mesh network over a forest. Technically it is not that hard and it is not that expensive. Get a bunch of wireless routers, put something smart in there to make them talk to each other and do multiple hubs, add one UMTS adaptor and you're done. The problem is of course that they all need power too and if you're going to put power lines to each of 'm, well then you might as well throw in a data line. That's why I think we should put USB adaptors on trees.
USB is not just nice for exchanging data; it also works great to power all these gadgets. So if we could somehow manipulate trees into powering USB outlets, we could do great things. It will probably take a while before Genetic Engineering gets to the point that this will happen automatically, but it should be possible to build some sort of USB plug that you hammer into a tree, connects with the tree juices and using a fuel cell convert this into electricity.
Sure we could work out something solar powered, but solar powered things tend to be very big and we like out gadgets small. Plus trees are big & solar powered and they look so much nicer than most other solutions.