The Price Comparison Tool by Volunteer Science enables you to see how corporations may be changing the prices you see based on factors like your browser cookies and user agent. Pages you visit on Google Flights, Amazon, Priceline.com, and The Home Depot (with more sites coming soon!) will be loaded on a remote server, and the server's prices will be loaded seamlessly into your page so that you can compare them. That's pretty cool, but the best part is that if you choose to donate your data, you'll be helping data scientists understand this phenomenon, called "price personalization".
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