According to the NYT, quantum computers, still in their early development, have reached the ten qubit milestone. To give you some perspective, a forty qubit quantum computer can perform ten trillion calculations, ten teraops, simultaneously. Forty atoms sitting in a nuclear magnetic resonance rig can rival the power of the largest supercomputers. A thousand atoms would solve problems currently considered intractable by conventional machines.
I’m still a little fuzzy on the theory behind quantum computers, and I consider myself very well informed, but I found this page that demystified things a bit.