Webisode

Mini-episode of a broadcast or cable series, available online or by other new media.

Examples:

Anime
  • Azumanga Daioh has a short web chapter that looks like Chiyo recording her class with a camcorder. In actuality, this webisode came out two years before the anime, and had a completely different cast (almost; Minamo's webisode voice actress went on to voice Yukari in the anime).
  • Haruhi-chan, a super-deformed Self-Parody of Haruhi Suzumiya.

Film

Live-Action TV

WesternAnimation
http://tvtropes.org/pmwiki/pmwiki.php/Main/Webisode