The OWASP ZAP core project
Scary good bug bounty & security distro with an installer to die for.
Sokoban with many families of puzzles provided.
Multi-core image resizer and rotator. Go crunch 'em!
Klotsky class block slider puzzles.
A C2 post-exploitation framework
Toolkit aimed to perform lateral movement in restricted environments
Perl Hacking Tools (BackTrack)