It's the weekend, which means it's time for the digital comics sales to begin. ComiXology is celebrating the February 28 release of Justice League: Doom with a sale on comics featuring the Justice League and their most notorious bad guys. Beginning tomorrow (February 25), 67 titles, including Mark Waid and Howard Porter's original 'Tower of Babel' storyline that is the basis for Doom will be available for $0.99. Other noteworthy titles on sale include Waid and Barry Kitson's Justice League: Year One, and Justice by Alex Ross, Jim Kreuger and Doug Braithwaite.