Spring are hosting their development sub-projects Maven repositories on S3.
This is a great idea if you are hosting a project that's likely to have downloads here and there and don't want to pay for what you don't use - which is what you'd be doing if you hosted it on a regular hosting plan.
(On a side note - if you're working on an open source project you may just as well host it on SourceForge or Google Code for free - even if your working on a commercial closed-source project there are free solutions - more on that in a future post)
The nice thing is that Maven has its own support for S3. Maven has a subproject that's responsible for the transport of artifacts called "Wagon". It allows maven to transparently work with repositories that reside on File, HTTP, FTP and other locations.
Wagon also has an extension that allows it to work with repositories on S3 - so it makes Spring's choice even better.
Browse Spring's Java Config project on S3:
Wagon-S3 artifact for Maven: