This is very, very cool. It allows you to deploy application logic extremely close to the user (in terms of latency), and Cloudfront has an order of magnitude

This is very, very cool. It allows you to deploy application logic extremely close to the user (in terms of latency), and Cloudfront has an order of magnitude more edge locations than the other AWS services like EC2 and S3. In fact, if the promised ability to read/write the request/response bodies does appear, it might be possible to deploy your entire website or app as a single Lambda@Edge function. (Not every app would fit within the size, memory, and CPU constraints, of course.) The main limitation would probably be the fact that for each incoming HTTP request, your choices are limited to either making zero origin requests (i.e. the function generates the response directly) or one origin request. It's not clear how this could work if you wanted to make two origin requests and combine them to render a single response. I'm totally going to sign up for the preview and play around with it! Especially if, like the regular node.js Lambda functions, you can include arbitrary Linux binaries with the function code. Compiled request-processing code would easily meet the 128MB/50ms criteria.