Bootstrap-like framework with focus on Google's Material Design look and interactions. Forms section is a great example of how nice it can look. Sass available, and several Javascript components.

Responsive. Style with CSS & control with JS. Usage of SVG. Other modern charting libraries I have posted about are Chart.js and C3.

Building a dashboard? Using Bootstrap? With maybe bar graphs, time charts, or maps? Why start from scatch? Use Dashboards by Keen IO templates to get you started.

No signup necessary, just pick a template, change text/images/link and download everything you'll need to send the email in a zip file.

A lightweight, easy-to-use jQuery plugin for fluid width video embeds.

Nodejs library to easily get screenshots of a responsive site at various resolutions; in your node script just specify the site and the size of screenshots and the directory to save the screenshots to.

Tables - they've got a bad wrap in web dev history, but it's appropriate for tabular data. Here's some neat plugins for making your tables more useful in responsive design.

Really nice responsive wordpress theme with portfolio, woo commerce, blog and forums (bbpress) built-in with lots of styling options for $60.

It's a set of small, responsive CSS modules. Just 5.7KB (smaller if you only use a couple). Includes a grid framework and styles for forms, buttons, tables and menus. It follows the SMACSS concept for modules. Use Skin Builder to customize the feel. If you think Bootstrap enforces too much of a particular look, this may be for you. Pure even works with Bootstrap JS modules.

Was on the hunt for a image slider carousel for a website over the weekend and had a hard time finding one I liked, which is surprising because all it's gotta do is rotate images with a fade effect and before and after buttons. I was impressed with the size of this one and how many stars it had on Github.