Before Amazon's announcement (which, because of the timing on March 31, led some people to think erroneously that it was an April Fools Joke), I had been working on an open-source barcode scanner.
Rather than be content with an SMS shopping list, I thought I could map the scan results to an online vendor's API, to enable scan-to-shop, a.k.a., lazy man's shopping.
Unlike the Dash button, you can pick any product, it would give you an opportunity to say no based on the price before ordering.
So far, the only vendor is Amazon (ironically enough) but I'm keen to add more, especially since Tesco in both the UK and Korea supposedly offer similar APIs, and there are probably other vendors out there that I'm not aware of.
Somewhat surprisingly, there is no good source of free barcode data.
The Open Product Data (POD) project is a promising start, but its catalog is limited, and they haven't published an update since early 2014.
Using PiScan is way of Contributing your individual scans and inputs back to POD, through another open data project I'm running at Saruzai.com.
But that's optional, you can use PiScan and just run your own server instead, which keeps your scanning history and collections private.
The software is available on github: https://github.com/Banrai/PiScan
The hardware is relatively straight-forward, with just a few things to buy, and no soldering or wiring required.
This parts list has two links for each item, the first is an affiliate link, which is a small way of supporting me to continue this work, along with a non-affiliate version underneath.