This set of APIs is Amazon's entrance into the geocoding market. They let you add location data and maps to your products. Use them to track the locations of physical assets (e.g. a fleet of trucks), get alerted when an item enters/exits an area, create a map of your store locations, plan trips, and more.

$0.04/map tile, $0.50/address geocoded

This API lets you access a vast archive of USA money-in-politics data. Use this create visualisations of how companies and politicians are linked, inform voters, or predict market movements. You can also use this API to get alerted when companies/sectors you are interested in are mentioned.

Free (donations encouraged)

This API gives you access to current and historical from the Apple App Store and Google Play Store from 155 countries. Use it to monitor the competition or spot global trends.

Free for 3,000 requests per month, then starting at $2,500 p/m

An API that provides live (~15 minute delay) oil prices and historical oil price data. Use this API to create price alerts, find historical trends between oil price data and pricing data of other commodities, show oil prices on relevant news site etc.

Starting at $9 per month for 10,000 requests per month