Koofas

If you had to give an estimate of the amount of weed you've smoked over your lifetime, how much would you guess?

I just watched Zero Days yesterday morning, and I was wondering if you could tell us a little bit more about Stuxnet. What was the feeling like when you realized how big of a deal it was? Also, I was really surprised by how much collaboration goes on between anti-virus guys, how do you keep something like that secure when you're dealing with something from a nation-state?

Hi Chris, I've always been fascinated with space and space travel, really from when I was a little kid. I was wondering, what is the hardest part about re-adjusting to Earth once you return from a long stay in micro-g? Also, I would like to know what you think about NASA's discovery of evidence of water on Mars.

Thanks!