jsDelivr's answer
jsDelivr is the only free CDN that aims to be production ready even for the most critical workloads. It has multiple failover systems for all of its components to ensure 100% uptime and uses multiple CDNs and datacenters for better performance.
cdnjs - An open source community driven JS/CSS CDN.
QR-Code Generator - QR Code Generator lets you create memorable marketing campaigns with trackable QR Codes—designed by you.
CloudFlare - Cloudflare is a global network designed to make everything you connect to the Internet secure, private, fast, and reliable.
The QR Code Generator - Free Online QR Code Generator to make your own QR Codes. Supports Dynamic Codes, Tracking, Analytics, Free text, vCards and more.
Statically - The free optimization & CDN for images, CSS, JavaScript, and open source.
QRTiger - The most advanced QR Code Generator with logo online