Xenon (Xe) - The cool-sounding knock-out drug of the future

• a noble gas that is heavier than air, possesses neither colour nor odour, and has revolutionized lighting
  
• xenon flash lamps helped make electronic flash, strobe lights (ugh), and very high speed photography possible
• makes good fuel for an ion thruster, a type of spacecraft propulsion that is best known to nerds everywhere as the thing that powers TIE fighters
• just for the record, star wars > star trek
• can be used to induce general anaesthesia, although it isn't used very often because it costs a heck of a lot to manufacture since it is so rare in the atmosphere
• is actually one of the best anaesthetic agents out there, so once we come up with a cheaper way of acquiring it expect it to find it on a surgical floor near you!
• it isn't yet understood how it knocks you out, but scientists have come up with two pretty good ideas:
• it blocks glutamate receptors, glutamate being the main excitatory brain signaling chemical (neurotransmitter)
• this is neat because most inhalational anaesthetics do their thing by stimulating GABA receptors, GABA being the main inhibitory neurotransmitter in the brain
  
• it messes with the levels of calcium ion (Ca2+) in neurons, leading to changes in the release of neurotransmitters because Ca2+ plays an important role in many second messenger systems
  
• is essentially inert in the body (its outer shell is full, so no need for other molecule's electrons), so it won't cause problems by forming covalent bonds with proteins and DNA, one of the issues with certain halogenated ether anaesthetics (see: halothane and liver toxicity)
• it somehow provides protection against ischemia-reperfusion injury to the cardiovascular and nervous systems that can occur during big surgeries
• like sulfur hexafloride, xenon lowers the pitch of your voice when inhaled, due to it lowering the resonant frequencies of the vocal tract
  

Preckel B et al. Molecular mechanisms transducing the anesthetic, analgesic, and organ-protective actions of xenon. Anesthesiology. 2006 Jul;105(1):187-97. Review.
http://en.wikipedia.org/wiki/Xenon