Here are a list of wonderful (and useful) JavaScript libraries that make your static site dynamic and cool.
(Above gif image from https://www.jstips.co/en/about/)
Ecommerce (can also used as a Favourite function)
- simpleCart: light-weight (<10 kb), customizable, international language, multi-payment support, easy to use.
Tooltip
- Tipr: just 2kb, easy to use and compatible with all modern browsers.
Mix and sort
- MixItUp.js: animated filtering, sorting, insertion and more. High performance.