TAS

TAS stands for either Tool Assisted Superplay, or Speedrun. A TAS is different from a regular speedrun as it's main purpose is to push a game to it's limit, exploiting the system on a level which is not normally humanly possible - but made so via use of an emulator, save states, and frame rate slow downs.
Usually a TAS manifests in the form of completing a game extremely quick - some graphical or frame rate glitches can be exploited so as to make a 15-20 hour long game (like Mario 64) completable in minutes.
I like them because they are fun to watch - and it's interesting to see what can be done to make the game shorter. Running through walls, getting damaged to move faster, anything is done to shave off a few seconds.

Also, you really have to admire the people who chose to spend their time making a TAS - an extremely repetitive job, that requires an utterly complete knowledge of the subject material (the game) not only on a control level, but a programming level too. They are therefore much more time consuming and difficult to construct than it is to simply play a normal speedrun, by a vast margine.

There are hundreds of them, all available on Youtube or Speed demos archive. I'm such a nerd, they really keep me engrossed. My favourites are usually the sonic ones. Some of them are played so well that it gives character to the sprites - a silent era movie style of character, in the way Sonic and Tails SHOULD have been portrayed in the cartoon series (and later 3D-era games). OK, I'm going to have to explain how they do this, so, new paragraph time.

Basically at the end of each stage it takes about 10 seconds for your score to be tallied. There is no exploit to make this go faster - so rather than just have the characters stand around and do nothing at this point (because they are still controllable) with the TAS both Sonic and Tails are given life. They jump around in synchronization, have play fights, every ounce of character possible is sucked out of those few animated sprites and put on screen. If there is one TAS I recommend any fan of Sonic or videogames to watch, it's this one:



It's really great how far they can push those sprites to act, I guess i'm probably looking into it way too deeply (geeking)
Anyway, here is a list of other good ones:

Super Mario 64
Super Mario Bros 3

Another thing that I like about TAS is how it transforms Mario from a rather clumsy, vulnerable, chubby plumber into a NINJA. In dungarees!

Zelda: A link to the Past
Zelda: Links Awakening
Super Metroid

Some games have even been edited just to show how items can be exploited, opening up a whole world of possibilities.

Mario World (Item Abuse)
Super Skill World


This website is awesome.