DVB-T tuner with USB interface which can be used as front-end for software radios. Found via http://www.ukhas.org.uk/guides:sdr_tracker

Interesting visualizations of irrational numbers.

PyEphem provides scientific-grade astronomical computations for the Python programming language. Given a date and location on the Earth’s surface, it can compute the positions of the Sun and Moon, of the planets and their moons, and of any asteroids, comets, or earth satellites whose orbital elements the user can provide. Additional functions are provided to compute the angular separation between two objects in the sky, to determine the constellation in which an object lies, and to find the times at which an object rises, transits, and sets on a particular day.

The numerical routines that lie behind PyEphem are those from the wonderful XEphem astronomy application, whose author, Elwood Downey, generously gave permission for us to use them as the basis for PyEphem.

Explanation of the risks of using JavaScript in Web browsers and e-mail clients (in german).

Interesting algorithm to invert functions, implemented in Common Lisp.

Quick notes regarding NIX system software issues, references to related work, ideas for future work, and any interesting result along the way. See the nix OS web site http://lsub.org/ls/nix.html

This tutorial is written in order to ease the transition from the very common and popular programming language Fortran 77 to the more modern Fortran 90. This transition uses the fact that Fortran 77 is a pure subset of Fortran 90.

An interesting algorithm for calculating complete elliptic integrals.
Alas, the link no longer works on 2020-03-10.

Fairly detailed description of a GPS receiver using 1-bit quantisation, down-conversion, despreading and tracking in an FPGA. The tracking loops are implemented in firmware on a custom Forth-based processor (in the same FPGA), the navigation solution is computed in a Raspberry π (http://www.raspberrypi.org/archives/3916).

Tahoe-LAFS is a Free and Open cloud storage system. It distributes your data across multiple servers. Even if some of the servers fail or are taken over by an attacker, the entire filesystem continues to function correctly, preserving your privacy and security.