IJCAI struck a deal with Elsevier, giving its associates free access to the Artificial Intelligence Journal (AIJ). Since it's possible to become an IJCAI associate at no cost simply by filling a web registration form, this effectively makes the AIJ a free resource.
The AIJ is not for the faint of heart: it's full of thick, math-ridden articles, on themes relevant to AI but clearly departed from everyday experience, even for the average software engineer. Yet, for those who are serious about following the latest developments in AI research, there is hardly a better resource.