pdflayer - Free, powerful HTML to PDF API supporting both URL and raw HTML conversion. Unlimited document size, lightning-fast and compatible PHP, Python, Ruby, etc.
Gource - Gource is a software version control visualization tool.
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request
Codeology - Open-source algorithm that visualizes GitHub projects
Tcpdf - TCPDF: Open Source PHP Class for generating PDF documents
The GitHub Matrix Screensaver - Latest commits from GitHub visualized Matrix-style