Since it's what the coolk kids are doing, I guess I'll list some of my ideas...

[u]SteamWorks:[/u] The user's body becomes a living boiler room. They can generate and hold vast quantities of superheated steam and vent it through their skin, often with explosive results.

[u]Weaver:[/u] The user has the ability to create, alter and control strands of silk secreted through their pores. 

[u]Battery:[/u] The user becomes a walking battery of sortsps, capable of absorbing and holding electrical energy. They may burn off this electricity to increase their physical might, or expend it directly to shock their opponents.

[u]Poltergeist:[/u] The user is a ghost, for all intents and purposes. They are intangible to the world, unable to interact with it outside of possessions. Maybe including some kind of telekinesis.

[u]Gelatin:[/u] The user's body is compromised of a semitransparent gel. They are able to manipulate its shape and properties at will.