I recently set up 2 email addresses for our girls. (FYI, you have to fib on their birthdate as they won't let you have an email account since they're so young...which is strange especially since Google initiated this idea) And whenever you have a second to write them a note, send a pic/video, whatever, you just email them. Anyone can email them too.
When they're older you can give them access to their account and read stories, notes, etc. I think it's such an easy way to journal about their life while sitting at the computer and forget about finding that journal while a baby is trying to steal your pen!