Internet Resources

SCIRUS: “the most comprehensive science-specific search engine on the Internet”
MIT OpenCourseWare: “makes the MIT Faculty’s course materials used in the teaching of almost all of MIT’s undergraduate and graduate subjects available on the Web, free of charge”.
MathDL: The MAA Mathematical Science Digital Library
MatLib: “a collection of mathematical software, papers, and databases.”
NDLTD: “Offers the world’s largest digital library of theses and dissertations of academic institutions worldwide”. 
NIST:    “provides information about activities and services at NIST related to applied mathematics, statistics, and computational science.”
Biographies of Women Mathematicians
MacTutor History of Mathematics Archive
Math Archive: A math resource hosted by University of Tennessee, Knoxville.
Math Forum : A “leading online resource for improving math learning, teaching, and communication since 1992”
Math World : A free source created and maintained by Eric Weisstein, with contributions from the world mathematics community.
WISE: Web Interface for Statistics Education