ACM digital library

The ACM is the Association of Computing Machinery, the American professional computer society. I've been a member before, but recently rejoined to gain access to their digital library, which I cannot recommend highly enough. Real downloadable conference papers and journal articles on every computer related topic under the sun. All, in pursuit of information for my two etcon/etech papers.
There is a free service, but it is limited to search and abstract only, joining the ACM is about 100 dollars, then I think it is better to join some SIGs rather than the library, I joined SIGCHI and SIGWEB and get access to all relevant papers via the two SIG affiliations. I've been feeling like an academic again, which is nice.