The original sources of MS-DOS 1.25, 2.0, and 4.0 for reference purposes

The Python programming language

DOSBox-X fork of the DOSBox project

BASIC for the modern era.

NES assembler and particularly clever disassembler

Open Source Computer Vision Library

List of awesome reverse engineering resources

An open-source user mode debugger for Windows. Optimized for reverse engineering and malware analysis.

Ultimate Commodore 64 Reference: ROM Disassembly, Memory Map, ...

An opinionated list of Python frameworks, libraries, tools, and resources

The fundamental package for scientific computing with Python.

Software to automate the management and configuration of infrastructure and applications at scale.

Visually explore Python object graphs

SciPy library main repository

Official repository for IPython itself. Other repos in the IPython organization contain things like the website, documentation builds, etc.

matplotlib: plotting with Python