First skin, made as a joke :P

Update Log:
Found a way to make it transparent, apparently if you change the char.png skin in the minecraft.jar instead of updating it to minecraft.net you'll have it tranparent. Only problem with that though, is the fact that noone will see it. :/
-Reason for Notch's disapproval on transparency-
-Invisible Griefers (That explains it all? For a definition on griefing look below!)

A griefer is a player who does things in a game to deliberately cause annoyance ("grief" in the sense of "giving someone grief") for the griefer's own enjoyment. Such a player is a particular nuisance in online gaming communities, since griefers often cannot be deterred by penalties related to in-game goals.^[2]

Exact griefing methods differ from game to game. Common methods include:

• Player killing in games that do not have separate areas, or an option, to keep those who want this type of gameplay from attacking those who do not.^[3] This does not include games that are designed with constant player combat in mind.
  
• Intentional friendly fire or deliberately performing actions detrimental to team members' game performance
  
• Any methods of reversing another player's progress (such as randomly destroying other player's creations in Minecraft or Terraria)
  
• Falsely accusing others of griefing behavior
  
• Written and/or verbal insults
  
• Stealing other players' items and/or experience (when done for the purpose of harassment, not self-gain)
  
• Spamming
  
• Camping at a corpse or area to kill someone as soon as they resurrect.
  
• Acting out-of-character in a role-play setting
  
• Saying or doing something just to irritate, upset, or otherwise harass someone
  
• Creating multiple subscription accounts
  
• Purposely not assisting the team (e.g. "feeding" (deliberately helping the other team by getting "killed"), wasting key game elements)
  
• Collusion with the opposition, referred to as "ghosting"
  
• Repeatedly trying to steal another player's kills so that their time is wasted
  
• Blocking another player's way so they cannot move or get out of a particular area, or access an in-game resource (such as a non-player character)
  
• Luring many monsters or one big one to chase the griefer and then rushing to where they want to unleash them. The line of monsters in pursuit looks like a train, and hence this is sometimes called "training".
  
• Destroying people's creations and/or flooding the location on a server is also known as griefing, mainly done in Minecraft or Terraria. There are many types of this sort as well, which includes many of the above (Such as annoying, out-of-character role-play, training, and stealing.)
  

http://en.wikipedia.org/wiki/Griefer - Credit goes to that
(Credit for that goes to Wikipedia, exact link: