Y'know, something people constantly ignore is the truely massive achllies heel that the Borg have, namely thier massive subspace communications system that they use to remain interconnected. Come up witha way to disrupt or jam that and the Borg are hosed for adapting and sending off information that would allow the rest of the collective to adapt.
My .02 credits
A brave little theory, and actually quite coherent for a system of five or seven dimensions -- if only we lived in one.
Academician Prokhor Zakharov, "Now We Are Alone"