Scott Buchanan is a Super Mario 64 challenge runner who can do amazing things in the game while pressing buttons as little as possible. Here's a 25 minute long video of him collecting the Watch for Rolling Rocks in Hazy Maze Cave star while only pressing the A button one half of a time.
Here is Let's Glitch Super Mario World, an in-depth series of 47 YouTube videos (each from 10 to 30 minutes long) that demonstrate breaking the game in myriad ways, with clear descriptions of what is going on.
Here's a list of things not to do in your Mario levels, consider it advice for when Super Mario Maker comes out in a week and a half. Also, here's things not to do in your Mario overworld. They both come from the rom hacking community at SMWCentral.
"Smashing...Live! was a live, orchestrated performance by the New Japan Philharmonic of many of the songs from the game Super Smash Bros. Melee. Unlike most other video game soundtracks, which are essentially recordings of game music, all of the pieces for Smashing...Live! are completely re-arranged and fully orchestrated." [SLYPlaylist] [more inside]
French group Golden Mustache contemplates the sex lives of various video game characters (video, English subtitles, surprisingly SFW, wait for Tetris)
Stephen Totilo of Kotaku tries to determine the correct chronology for all the games in the Super Mario canon.
PETA's latest public target is Super Mario 3D Land, specifically Mario's use of the tanooki suit, which PETA claim signify the wearing of a tanuki skin. To raise awareness, PETA had a little flash game made: Mario Kills Tanooki (warning: cartoon blood and gore), in which you play a skinless Tanuki trying to get your skin back from Mario (YT, 1:19 - slightly stuttery gameplay video). But as this Kotaku article points out, PETA's outrage is "an epic culture misunderstanding," overlooking the long, cultural history of the shape-shifting trickster. Nintendo's quick response: "Mario often takes the appearance of certain animals and objects in his games," that are "lighthearted and whimsical transformations." PETA clarifies: the graphic little game was just a joke.
Violinist plays the music and sound effects of NES games. Donkey Kong. Dragon Quest III. Super Mario Bros 3. [more inside]
Mario Adventure - SMB3 hacked into an entirely new high-quality game
SMW - The complete soundtrack to Super Mario World, covered by one man using dozens of instruments. Roughly in game order, faithful to the originals, with some bizarre artistic license thrown around. A private hobby made public. Dedicated to Koji Kondo.