H2OGfat

H2OGfat is the liquid used to keep bodiless heads alive in jars. It is apparently high in nutrients and while refreshing to drink, results in timetraveling to the inhabitant's era in history, as seen in "All the Presidents' Heads". This is due to trace amounts of powdered crystalline opal, a preservative. The name was first shown in Bender's Big Score.

Trivia
When Hank Aaron XXIV drank from Wade Boggs's head in a jar he did not go back in time.

Appearances

 * Since heads in jars appear in almost every episode, so does this fluid, we only list the obvious appearances here.