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Over the last year, Matthieu Aussaguel has been blogging a series named "Can you Code this UI Concept?" in which he finds user interface ideas that exist as GIFs, and then an implementation of that idea in real code. The implementations are already done in these posts, but it doesn't mean you still can't think of the originals as a challenge and try to build it yourself.
Here's an example from each of the five volumes he's published so far.
Coded by Nikolay Talanov:
Coded by CODEARMADA:
Coded by Ryan Mulligan:
Coded by Ken Chen:
Coded by Varun Vachhar:
The idea is similar to Give 'n' Go.