The NRF24L01 wireless transceiver is a great device for adding a simple wireless interface between two Arduino boards or other similar systems. The ESP-01 presents even more capabilities, as a WiFi breakout for the ESP8266 in a similar form factor. To facilitate prototyping with either one using a breadboard, Tindie seller Electroboffin came up with an 8-pin breadboard adapter for the NRF24L01 and ESP-01.
While this might seem trivial or unnecessary, if you’ve ever used one of these modules, you know that hooking it up to a breadboard generally results in a messy jumble of wires. This adapter instead breaks out either board’s 8 pins into a nicely-spaced arrangement for breadboarding, which is able to straddle the middle breadboard gap for easy connections.
One could see it being especially useful for projects involving an Arduino Nano, Pro Micro, or similar devices, where the dev board plugs in directly to the breadboard. It’s a very simple device, but one that should save a lot of hassle and wiring ugliness.
For another NRF24L01 idea, you might also check out the USB RF gateway/development device featured here.