For a few projects I like to use 7 segment displays to indicate a value like voltage, current or temperature. 7 segment displays are cheap, easy to read and easy to control. The biggest downside is that it can cost a lot of IO pins on a uC to control a handful of 7 segment displays.
One option is to buy finished 7 segment displays on Ebay that can read in a voltage. The downside of these is that the accuracy is not great and they can only be used if a certain range in voltage is what you want to display.
So time to design my own, yet another seven segment display, or YASSD for short. They have a 4 digit 7 segment display on one side and a STM32F031 and a 74HC595 on the other. Other features are:
Maximum of 8 on one UART bus, an ID is selected via 3 solder bridges
Easy to mount on a frontpanel
No programming hardware needed, just a UART to program them.
More info can be found on my blog, link is listed in the project information