This is a horribly sad event. My heart goes out to everyone involved - victims, families, everybody.
I ran Boston a few years ago (the same day of the Virginia Tech massacre). I'm not trying to make this about me, but it's weird thinking about how in that race my mom and brother were standing along Boylston St., close to where the explosion further away from the finish occurred. Just people watching a race...
I really don't have words for this. Sickened and upset. To quote Boyz n' the Hood, "We're living in a violent world."