Patterninja - Create patterns online
Paaatterns - Free collection of beautiful patterns for all vector formats
Doodad.dev's Pattern Generator - A free tool for creating unique, royalty-free, repeatable patterns.
Layer CSS - Lightweight CSS framework to build your own fluid layouts
SVG Stripe Generator - SVG Stripe Generator is an easy-to-use tool that enables you to create unlimited stripes and then download them to the device.
Vectorizer.io - Fast and easy way to vectorize an image online