The T-95 Super Heavy Tank was a prototype heavily armored tank destroyer class designed to fight heavy German tanks and later expected to break through enemy defenses at the Siegfried line. Conceived in spring of 1945, it was put through trials successfully but was built too late for use in WWII.
Video of trials:
More reading at: http://en.wikipedia.org/wiki/T28_Super_Heavy_Tank
(Don't kill me if this post is shitty)