I just came across this blog post: http://www.satine.org/archives/2007/12/13/amazon-simpledb/. The author got the scoop that Amazon's just-released SimpleDB runs on Erlang. This is actually the second Amazon Web Service that runs on Erlang -- at least, if the rumors I've heard that Amazon SQS was built with Erlang as well are true (update: I found the reference in this article).
It's pretty cool knowing that you can use the same language that powers some of the massive systems that Amazon and Ericsson have built to whip up a blog app just as easily as in Ruby or Python. (But if you built it in Erlang/ErlyWeb, you could also use Comet to make the blog update itself in real time, resting assured that horizontal scalability is just a matter of reconfiguring your Mnesia schema :) ).
Amazon SimpleDB is a game changer. It fills the last hole in making Amazon Web Services a complete environment for elastic, scalable web application hosting: the need for a fast, reliable data store. Together with S3 and EC2, SimpleDB makes it feasible for small startups to scale like the big companies but without the operational overhead. What a great set of products from Amazon.