Because it employed parallel processing to attack its problem, the Colossus machine was enormously powerful. Even today, a desktop PC would take a similar amount of time to crack a Lorenz key... It was the first ever programmable electronic computer, predating the American Eniac (Electronic Numerical Integrator and Computer) by two years.
A forgotten piece of history, brought back to memory by the sale of an original Enigma on eBay today. Bidding is still open, but it's up to $48,700 now with over four hours left.