An author who wants to give away their work currently has a lot of venues to do so, including Feedbooks, Smashwords, the Kindle Store, and they can even set up their own website. Last week Project Gutenberg threw another option into the mix. It hasn't gotten any serious amount of attention yet, but Project Gutenberg is now letting authors upload and distribute their own works. The new site can be found at self.gutenberg.org.
The new site currently has 677 titles, and it doesn't quite operate under the same rules as the Project Gutenberg main site. It's being run independent of the main site (search doesn't cover both), and while the 40,000+ titles on the PG main site are in the public domain (and thus can be freely shared), the ebooks offered via the new site are still under copyright. What's more, not all of the titles are offered under a Creative Commons license.
You can still download the ebooks; you just cannot share them. This not so subtle distinction should appeal to some authors; they still have the option of adding a CC license to their ebooks if desired.
I have to say that I have mixed feelings. Yes, it's a good idea to offer this service, and it ties nicely into PG's own free ebook downloads, making it easy for authors to attract the attention of readers looking for freebies.
But I do wish they'd offer some format other than PDF. Say what you will about the format being supported on almost every device, it's still not supported well on the Kindle or a number of other ereaders. I'd much rather have Kindle or Epub as an available download.