Now, I can see calling a MasPar a "parallel supercomputer"; another effort at the SSL challenge got the answer about 2 hours before Damien's did, and used about 4 days of spare time on the MasPar. Last time I looked, a MasPar was selling for about $150K, though I don't know how big the one used on SSL was. At that price, you could have your own for ~$500/day, and ripping off $2000 on a credit card isn't tough in today's automated world. Next year - computer time costs half as much.
Well, lets put it this way, an MP-2 with 16K processors could attack a 56 bit key about as fast as a 486 could attack a 40 bit key. The next generation MP will be less than an order of magnitude faster, although able to use more processors. An MP2 with 1K processors can do 220K crypt(3)/sec. Now, if it weren't so darned hard to program one for performance... One tends to wonder if there are analytical methods to reduce the search space.