Super conductors are conducting compounds that have zero electrical resistance and no internal magentic field. A few have been found, and in the 80s the critical temperature was around 92 Kelvin (-181 Celcius).
EDIT: apparently the highest critical temperature is 138 K (-135 C), which is a thallium-doped, mercuric-cuprate comprised of the elements Mercury, Thallium, Barium, Calcium, Copper and Oxygen.
Still a long way to go, and I doubt we will ever have a room temperature conductor with zero resistance, but it's a nice thought.
(spot the chemistry student...)