I like this approach to offering a design system. It seems less prescriptive than many:
Designed not as a rule set, but rather a toolbox, the Data Design Language includes a chart library, design guidelines, colour and typographic style specifications with usability guidance for internationalization (i18n) and accessibility (a11y), all reflecting our data design principles.
A very handy collection of design exercises as used by 18F. There’s a lot of crossover here with the Clearleft toolbox.
A collection of tools to bring human-centered design into your project.
These methods are categorised by:
- Discover
- Decide
- Make
- Validate
- Fundamentals
A handy microformats toolkit from Microsoft(!) making it easier for developers to write, style and find microformats (hCard and hCalendar in particular). Neat!
Christian's wish list for JavaScript libraries.