Stanza: It’s a wireless electronic library that stays open 24/7.

http://www.lexcycle.com/

"Stanza is a free application for your iPhone and iPod Touch. Use it to download from a vast selection of over 100,000 books and periodicals, and read them right on your phone...

Forget carrying around stacks of books for school, work, or vacation. Stanza on your iPhone or iPod lets you hold a lifetime’s worth of reading in your pocket or handbag. Whether on a plane or waiting in line, your books are only a tap away...

Have an existing collection of electronic books? Have documents you want to view on your iPhone? Move them onto Stanza iPhone/iPod by using the free Stanza Desktop application for Mac & PC."

FYI, Stanza was acquired by Amazon.com.