Douglas N. Arnold, Professor of Mathematics at Penn State University, has developed these graphical demonstrations to enrich his first-year calculus courses. An online, interactive textbook for Real Analysis or Advanced Calculus in one real variable. Calculators and Unit Conversions Martindale's Calculators On-line Center is an extensive collection of online tools for calculation and conversion. The many choices offered run the gamut from using an abacus or a slide rule online or calculating equivalents for all kinds of measurements, to evaluating everything from differential equations to Delaunay triangulations. You can also try out over 130 statistical calculators.
Many online calculators require a java-capable browser.
Entisoft's Measurement conversion Calculator will perform over 500 different unit conversions for distance, area, volume, mass, speed, temperature, pressure, energy, power, force, etc. The Geometry Junkyard - David Eppstein, Theory Group, ICS, UC Irvine. A collection of usenet clippings, web pointers, lecture notes, research excerpts, papers, abstracts, programs, problems, and other material related to discrete and computational geometry - some serious and much also entertaining. Also see Eppstein's other pages, Geometry in Action, which is devoted more to applications and less to pure math, and his non-geometrical Recreational Math area. Alexander Bogomolny's Interactive Mathematics Miscellany and Puzzles .