This site provides a free physics textbook that tells the story of how it became possible, after 2500 years of exploration, to answer such questions. The book is written for the curious: it is entertaining, surprising and challenging on every page.
remaking the classic 1984 arcade game Marble Madness by Atari. The graphics are slightly enhanced to bring them on par with modern standards: there is now a full 3D mode in addition to the usual isometric perspective one
quickly compares multiple documents searching for copied and pasted fragments of text. Suspicious findings are reported in the convenient format that shows just what you need to see. Plain text, HTML files, and numerous word-processing formats supported
an application that lets you monitor TCP and UDP activity on your local system. It a powerful tool for tracking down network-related configuration problems and analyzing application network usage.
A bit more feature powered than Zamzar. With more formats and a bit more complicated interface. However, I can guarantee you that it’s worth the usage. No email needed. 100Mb limit
an online accessibility testing tool designed to visually convert a full-color web page into a grayscale rendition for the purpose of visually testing the page’s perceived contrast.