Here's a fun way to amuse yourself on this damp Tuesday morning: Supper Mario Broth, an old tumblr page that's full of cool Nintendo art, screenshots and trivia. For example: did you know that Super Mario Bros. 3 has an animation that you can only see if you get the Hammer Suit when you're in the process of sliding? (h/t Chris Kohler)
As Supper Mario Broth explains, you can't actually slide down a hill while you're wearing the Hammer Suit -- ducking to slide will just make you go into your shell. But Nintendo made an animation for the Hammer Suit's slide, just in case you happen to get the power-up while you're already on a slope.
Rad, don't you think? Another fun fact: one of the doors in Super Mario Galaxy was actually a sign.