One of the side projects I work on is Baconfile, a web interface for Amazon S3. This weekend I fixed up the (previously semi-functioning) Baconfile API. The API now allows you to not only get data for files and folders, but to post new content to Baconfile. Find out more about the Baconfile API here.
The first real project to be built on the API is Bacondrop, a Mac uploader for Baconfile. Bacondrop is nice and simple - just drag any file over to the Bacondrop app (or dock icon) and the file is instantly uploaded to your Baconfile account. You can download the latest Bacondrop here.
If you're interested in building your own Baconfile app, there's also a nice Python library by joshthecoder on GitHub.
