tcS3 — Upload directly to Amazon S3 from your WordPress install
Amazon’s inexpensive, unlimited cloud storage system is an excellent asset backend for all websites and this all-inclusive plugin uses the AWS SDK for PHP to facilitate uploads directly from your WordPress instance to your S3 bucket. This plugin requires nothing special from you — it has been tested for performance on shared hosting, VPS and dedicated servers and worked on each, out of the box, both on Apache and nginX. tcS3 has been tested on wordpress 3.7 – 4.0 and worked well on all versions.