Web calculator implemented in JavaScript. Implements arbitrary precision, plotting, prime testing, polynomial roots, matrix arithmetic and very limited (polynomials) symbolic integration. Written by Fabrice Bellard, who also wrote TinyCC, QEmacs, FFMPEG, QEMU and more: https://bellard.org/

Some software for dealing with Mac OSX metadata, including backup to a remote, non-OSX, unix machine.

Lots of information about Lisp.

Blog written by Juan Jose Garcia Ripoll, maintainer of the Common Lisp implementation ECL.

Interesting information about phase noise.

rsnapshot is a filesystem snapshot utility for making backups of local and remote systems. Using rsync and hard links, it is possible to keep multiple, full backups instantly available. The disk space required is just a little more than the space of one full backup, plus incrementals. Depending on your configuration, it is quite possible to set up in just a few minutes. Files can be restored by the users who own them, without the root user getting involved. There are no tapes to change, so once it's set up, your backups can happen automatically untouched by human hands. And because rsnapshot only keeps a fixed (but configurable) number of snapshots, the amount of disk space used will not continuously grow. rsnapshot is written entirely in Perl.

A book trying to teach computers from first principles, i.e. gates, using a hardware description language (a simulator is provided), software tools (assembler, compiler) and a small operating system.

Asynchronous, multi (40!) core Forth-bases processor with fast ADC and DAC interfaces, might be interesting for software radio applications.

Java-based simulator for digital logic, with examples.