This past week there was a flurry of blog posts about deploying and accessing geospatial data in "the cloud." Yes, I'm still putting scare quotes around "the cloud" in 2017.
I wrote a post specifically about Rasterio and datasets on S3 last December. Shortly before that, Chris Henrick wrote a great post about preparing data to be deployed on S3 for use with GDAL and Rasterio.
As far as I can tell, the birth announcement for geodata in the cloud came 7 years ago in "VSI Curl Support" by Christopher Schmidt.
It's remarkable that the authors of HTTP/1.1 foresaw this kind of application in 1999: https://tools.ietf.org/html/rfc2616#section-14.16.