from the site:
"Tardigrades are a fascinating group, and have an ability to withstand extreme conditions in a desiccated barrel-like form called a 'tun'. In this form they are one of the most resilient types of animal known. Temperatures as low -272ºC (i.e. almost absolute zero) or as high as 151ºC; X-ray radiation 1000x times the human lethal dose; high vacuum - conditions all taken in the stride of the not so humble water bear. When a piece of dried-up moss which had been kept in a museum for 120 years was moistened, tardigrades successfully recovered from the 'tuns' in the moss.
Recent research has notched up another feat of endurability, apparently they can withstand 6000 atmospheres pressure, which is nearly six times the pressure of water in the deepest ocean trench (see 'New Scientist', 31 October 1998, p. 26)."pretty wild stuff, and a cool little video, too!
