Websites: camelcamelcamel: Amazon item price history

camelcamelcamel is a cool (surprisingly, camel-branded) free online service to check the actual and past prices (historical prices, price dynamics etc.) for items on Amazon online marketplaces (including the regional sites).
For example, here is a link to the Amazon price history for the Fifty Shades of Grey (paperback book; somewhat NSFW, sorry):

• Fifty Shades of Grey: Book One of the Fifty Shades Trilogy (Fifty Shades of Grey Series) (0345803485) | Amazon price tracker / tracking, Amazon price history charts, Amazon price watches, Amazon price drop alerts | camelcamelcamel.com

---
Last updated: 2019-09-10