Children of Mars 50% off sale to celebrate its first birthday:
I really highly recommend this, it's a great piece of science fiction.
Generation One: Children of Mars is an independent comic book series about the first generation of kids born on Mars. Since its Kickstarter campaign, which raised over $30,000, Generation One has gone on to secure endorsements from The Mars Society, The European Space Agency, Dr. Armin Ellis of NASA’s Jet Propulsion Laboratory, and Dr. Robert Zubrin, author of “The Case for Mars.”
This 110-page full-color paperback graphic novel contains a 3-issue core story, a Halloween bonus issue, a making-of section, and an appendix full of awesome info about Mars and the science behind the comic.