Windows: If you're looking for a quick and simple way to generate a flowchart, Diagram Designer is a free and lightweight tool for easy flowchart generation.
Diagram Designer offers easy chart creation with a library of flowchart nodes and connectors. Text in each element is customisable with a variety of tags and connectors automatically attach to points on each node. Every element is scalable, and your charts are exportable in a variety of formats like JPG, PNG and more.
Diagram Designer supports customisation of nodes and importing of image files to the flowchart, but it really shines with quick barebones flowchart creation. Diagram Designer is freeware, Windows only. Have a favourite flowchart application online or off? Let's hear about it in the comments.