title: Parallel arbitrary-precision arithmetic library
body: <p>I am trying to do modular exponentiation of integers with a very large modulus by repetitive squaring (the power is always a power of 2 in my case, so I believe this is the most efficient way).  Thanks to a nice property of my modulus, computing remainder is cheap; the hard part is multiplication.</p>
  
  <p>Currently I run GMP on Intel Core 2 Quad.  I would like to make efficient use of the four cores of the processor, but GMP does not scale on SMP environments, so I am looking for a substitute arbitrary-precision arithmetic library.  I have found some libraries for parallel computation on <em>matrices</em>, but what I really need is a library for <em>integers</em>.</p>
  
  <p>Does what I am looking for exist?</p>