LICEcap can capture an area of your desktop and save it directly to .GIF (for viewing in web browsers, etc) or .LCF (see below).

LICEcap is an intuitive but flexible application (for Windows and now OSX), that is designed to be lightweight and function with high performance.

LICEcap is easy to use: view a demo (output is here).

In addition to .GIF, LICEcap supports its own native lossless .LCF file format, which allows for higher compression ratios than .GIF, higher quality (more than 256 colors per frame), and more accurate timestamping. If you record to .LCF, you can play back the .LCF files within REAPER (and/or use it to convert to .gif or another video format).

LICEcap is GPL free software, each download package includes the source.

A large quantity of published data is available only in the form of plots and it is often difficult to extract numerical data accurately out of these pictures. There are several softwares available to aid this process, but most are either paid, difficult to use or lack some essential features. Also, many of the existing programs work only on a few specific operating systems and require installation by the user. Most programs only support 2D X-Y plots and so it is not possible to work with polar diagrams, ternary diagrams, microscope images or maps. With these issues in mind, WebPlotDigitizer was developed to be an easy to use, free of charge and opensource program that can work with a variety of plot types and images. This program is developed using HTML5 which allows it to run within a web browser and requires no installation on to the user's hard drive.
Distributed under the GNU General Public License Version 3.

Found on John D. Cook's blog
http://www.johndcook.com/blog/2016/04/20/how-to-digitize-a-graph/

Changed URL from http://arohatgi.info/WebPlotDigitizer/ 2019-12-30

So I found out about pdf tools, which is a replacement of docView for pdf files. It essentially turns the pdf into a png file. It's SOOO fast, and you can search for text inside the document!
Does not work on windows.

Tutorial about git for people familiar with CVS.

A highly secure, comprehensive, easy-to-use replacement
for usernames, passwords, reminders, one-time-code
authenticators . . . and everything else.
The site contains other interesting things such as a TrueCrypt repository, password generators and other tools and information about the PDP-8.

Tool to analyse the dependency of Windows programs on dynamic libraries.

The Purely Functional Package Manager

Nix is a powerful package manager for Linux and other Unix (including OS X) systems that makes package management reliable and reproducible. It provides atomic upgrades and rollbacks, side-by-side installation of multiple versions of a package, multi-user package management and easy setup of build environments.

On-line tool to learn about cryptography. Supports a number of encryption methods (including Enigma).
An off-line version can be found on http://www.cryptool.org/

A description how to use the MinGW-w64 tools in Cygwin.

Zero Install is a decentralised cross-distribution software installation system. Other features include full support for shared libraries (with a SAT solver for dependency resolution), sharing between users, and integration with native platform package managers. It supports both binary and source packages, and works on Linux, OS X, Unix and Windows systems. It is fully Open Source.