Lately, I've been working on the theming system of Kendo UI for Angular. The system has turned out rather nicely, providing a hefty set of features that we could not ship previously. One of the elements that allowed this is the (surprisingly simple) dependency infrastructure.
Ever wondered which color transition function to use to get from one color to another? Ever wanted to create a site without hard-coding all similar colors?
Imagine that you need to borrow a hosted CSS file, along with its resources. You paste the CSS contents in a text editor, and start searching for url() patterns within it. After seeing 100+ matches, you bless the name of the CSS sprite-oblivious person who built it.
Quite a bit of people find the default vimtutor too static for their learning style. Here's a list of sites that let you learn Vim in a more interactive way.