S3BucketApp is a python application running on Google App Engine which implements the Amazon S3 compatible REST API access to the internal storage of GAE (Google's BigTable).
If you install S3BucketApp into your App Engine slot, you will be able to save practically unlimited number of small files (less then 1 MB - GAE limits) into App Engine with tools developed for S3 storage.
Such files are available trough the webbrowser, so Google App Engine platform act a webhosting for static files or (to be more precise) a scalable global content delivery network (CDN) for small static files.
The target is provide from GAE a fast and stable content delivery functionality with compatibility for the existing S3 tools like:
s3cmd - general tool to work with S3 s3funnel - multi-threaded upload/download for small files and usage with unix pipe s3backer - virtual hardisk for linux/mac s3fox - Firefox plug-in for visual browsing in the S3 buckets In this moment project is in the planning phase, the main reason for development is a need of tile hosting for application MapTiler - Google Maps tiles generator.
An advantage of the Google App Engine file hosting against Amazon S3/CloudFront is that you control the processing of the requests, so you can implement custom protection of the files, versioning of the tile trees, or dynamic processing (for example merging with caching) for the images, etc.
Note: there is another project implementing complete Amazon S3 emulation on the Google App Engine: Baltic-Avenue. S3BucketApp should implement just one S3 bucket and subset of the AmazonS3 functionality, with preference for speed of delivery of the content (GET operation) and simplicity.
These details are provided for information only. No information here is legal advice and should not be used as such.