The Gherkin is a fun-sized keyboard project. With 30 keys, it offers a compact ortho layout that fits all of the alpha keys and a few mods in the base layer.
With a bare PCB, it is also a good kit to practice/learn soldering with. You'll learn to solder diodes, switches, and a Pro Micro board. The PCB is also compatible with the Elite-C board, which can be bought from other vendors.
Once built, you can flash QMK software and customize your very own layout. I personally enjoy using my Gherkin as a large macropad to have a lot of quick shortcuts to commonly used functions such as volume control and function keys.
USB cable (specifically, micro USB if using the Pro Micro)
The Gherkin is an open-sourced design and is being sold under the CC BY-SA 4.0 license. It was created by the awesome people at the 40percent club. They even have a great build guide for putting together your kits which can be seen here.