Polywater

Polywater is a theoretical version of water that, through heating to boil and letting to cool in quartz capillaries, could re-structure itself and become more viscous and have a higher boiling point and lower freezing point. It was first brought to the public in a lecture in England by the Soviet scientist Boris Valdimirovich Derjaguin, who claimed that Soviet scientists had already discovered how to create polywater, which is not surprising seeing as this was during the Cold War and was probably meant to strike fear in those who opposed the USSR.

Citations:

http://www.cs.cmu.edu/~dst/ATG/polywater.html

http://itotd.com/articles/588/polywater/