Ordering a taxi should be as easy as purchasing things from Amazon, right? That's what we made to our office lobby.
Pressing the button orders an SMS taxi to our office. Display shows order status and after taxi confirms the order, taxi number.
List of parts:
In total about 310€ plus small desktop computer and display. Our display also shows bus timetables for nearby bus stops and weather information for our offices in Helsinki, Tampere and Berlin. Bus timetables require HSL API key. Weather information uses weatherbug API.
We put up github repository for the code with some very short instructions. Whole system was put together just before our annual party, so it's not particularly production quality code. It's licensed with GPLv3, so feel free to use and modify it.