I have an iPhone with a couple of book reader apps (including kindle). Several of my coworkers have Kindles. None of us have paid for any books yet.

There are lots of sources of free books available on line depending on your needs/tastes. Project Gutenberg has lots of free books that are no longer protected by copyright. Several publishers offer free samples including, Random House, Harlequin and Baen. There are lots of other sources as well.

Currently I have about 147 books on my iPhone. Convenience factor is very high and the battery has lasted through a full 14 hour day of travel, lots of cell phone calls, some web surfing and at least 6 hours of book reading with the music playing. It won't run for days on end without a charge, but neither will I.

Hope that helps,

- Eric