eFunda.com ========== There is a nice site for structural engineers: the efunda.com. I work in a related area (in civil engineering) so I sometimes visit the site to find some formulas and other information. The site is here for ages and it has one great advantage: it is NOT modern. It means that it is accessible (and usable) even from old WWW browsers (the Netscape 3.x is a good example) including most of their on-line calculators (!). That's an extremely rare thing in today's WWW. I hope that they will survive in this form for a long time... References: [1] http://www.efunda.com