Best AMAs on Reddit

Microsoft Chairman Bill Gates gave Redditors his definition of "hanging out" in February.

Question: What do you do for fun? I find it hard to fathom how someone like you can just disconnect. Disconnect from the emails, calls, the media, all of it. What would be your definition of a chill and fun day?

thisisbillgates: I love playing tennis. I am an avid bridge player (a card game if you have not heard of it — it was more popular in the past!). I like to tour interesting things with my kids like power plants, garbage dumps, the Large Hadron Collider, Antarctica, missile Silos (Arizona) . . . I read a lot and watch courses (online or The Learning Company.)

Bill Nye (the Science Guy) chatted about science's role in everyday life in July 2012.

Question: Is/was science a part of your everyday life? Also, I love you.

sundialbill: Science is part of everyone's everyday life. Hard to find anything lovelier than a tree. They grow at right angles to a tangent of the nominal sphere of the Earth. They take water from the ground toward the sky. They are made mostly of carbon . . . which they take in right out of the air. How cool is that . . . and so on and on and on and on and on and on and on . . . .

How awesome is it to see Earth from up above? Chris Hadfield, an astronaut for the Canadian Space Agency, answered in December 2012.

Question: What does it feel like to look down on earth during a space walk?

ColChrisHadfield: It is wildly beautiful, the colours and textures, the global view, the chance to have the Northern Lights ripple under your feet. Stupefying

Screenwriter, producer, and director Joss Whedon (The Avengers) talked about his writing process in April 2012.

Question: Hi Joss. Do you use techniques to boost your creativity for writing? Do you for instance write better when you meditate, exercise, take alcohol, etc.?

IAMAJossWhedon: I like movie scores. They really help put me in the moment, no matter where I am. Avengers owes a lot to Rachel Portman's Never Let Me Go and Hart's War . . . And I do like a reward for writing — cup of tea, glass of wine, meth-fueled crime spree . . . but when a story has me, I don't need anything but a pen.

Ken Jennings, 74-time Jeopardy winner, talked about his mullet fears in March 2011.

Question: What category would be a nightmare for you?

WatsonsBitch: I remember country music kept showing up. That or hockey. Least favorite categories. Basically anything with a mullet is my Jeopardy kryptonite.

In a sea of technical questions in January, statistician Nate Silver talked about his other hobby.

Question: Are you ever going to finish your Burrito Bracket Project?

NateSilver538: Perhaps I can convince Penguin that my next book should be a 256-taqueria burrito bracket with entries from all across the country.

In November 2011, astrophysicist Neil deGrasse Tyson talked about what leaves him awestruck.

Question: What is your favorite fact about the universe?

neiltyson: That it will never end. That it's on a one way trip of expansion. Something that many find to be philosophically unsettling. My view is that if your philosophy is not unsettled daily then you are blind to all the universe has to offer.