Handsome Illustrations - Create unique illustrations for websites & applications.
StatusPage.io - StatusPage.io is the best way for web infrastructure, developer API, and SaaS companies to get set up with their very own status page in minutes. Integrate public metrics and allow your customers to subscribe to be updated automatically.
Control Illustrations - 108 free flat illustrations with customizable characters
Trendy 404s - A set of creative templates for your 404s
Ouch! Illustrations by Icons8 - Professional, perfectly matching, and customizable illustrations for any designs
FourZeroFour - Showcase of the best error pages on the web.