This tutorial will cover digital shipping scales! I know, exciting, right? But really, if you need to sense weights and get them into a computer or microcontroller, these are really easy to find, fairly accurate and easy to use.
We use digital shipping scales for our shipping system (no surprise there!) - we weigh every package to make sure we are purchasing the right amout of postage. For postal, if we dont put the right postage on, the package can get returned or denied which is no good. We could try to approximate the weight from knowing whats in the order but packaging can vary - this way its always perfectly known when we buy the postage!