All of them:

http://www.reddit.com/static/reddit404a.png http://www.reddit.com/static/reddit404b.png http://www.reddit.com/static/reddit404c.png http://www.reddit.com/static/reddit404d.png http://www.reddit.com/static/reddit404e.png

Aww, some pages just make you want to hug their creators. I wish more sites had this kind of warm gems.