Free up as much hard drive space as you can. Marvel Comics is giving away 700 first issues – including many from the newly launched Marvel Now brand – on Marvel's digital apps and Comixology. I highly recommend checking out All-New X-Men, Iron Man, Uncanny Avengers, and any classic event like Infinity Gauntlet, Civil War, and Fear Itself.

These digital sites are experiencing high traffic at the moment (duh) and are understandably experiencing problems. I've been able to select the comics I want for download, but any attempt at getting them has been hit with a "download error" message. I would say wait, but the promotion only runs until Tuesday, 11 PM Eastern Time. At least get the comics you want queued up for download. Happy shopping!