I made some test meek bundles that are capable of using the Amazon CloudFront CDN as a backend, in addition to Google App Engine that was supported before.
https://people.torproject.org/~dcf/pt-bundle/3.6.3-meek-2/
https://trac.torproject.org/projects/tor/wiki/doc/meek#AmazonCloudFront
To test it, go to the pluggable transport screen, and choose "meek-amazon" from the selection box.
meek is a pluggable transports that hides the true destination of your communication (a Tor bridge) by hiding it behind a different domain name. When you select meek-amazon from the list, your traffic will appear to a censor to be going to the domain a0.awsstatic.com, but will actually be going to a Tor bridge on cloudfront.net.
I signed up for the Amazon Web Services free tier, which limits use to 50 GB and 2 million HTTP requests per month. Please feel free to use it, but don't depend on it not going away. If it becomes too expensive, we'll have to shut it down until we can find a way to fund operation long-term. (The same goes for App Engine, BTW.)
David Fifield