Usability 
Project Gutenberg now has its own mobile webapp at m.gutenberg.org. The project, which is celebrating its 40th anniversary in 2011, creates free eBook editions of books that are out of copyright or were published under a license such as Creative Commons that allows them to be distributed freely. The catalog currently has over 36,000 titles.
Dubbed "PG Mobile", the mobile version carries the entire Gutenberg catalog. Author, title and subject search makes it easy to find your favorite authors and books. If you are looking for reading suggestions you browse listings of the most popular and newest titles or visit category "Bookshelves" like "Harvard Classics", "Detective Fiction", "Banned Books" or "Erotic Fiction".
Project Gutenberg's mobile view appears to be optimized for the iPhone and other touch smartphones but degrades nicely in lesser browsers and worked well when tested with the Myriad (formerly Openwave) browser of a basic feature phone.