  Realizing the extraordinary scientific potential of the CMB requires precise
measurements of its tiny anisotropies over a significant fraction of the sky at
very high resolution. The analysis of the resulting datasets is a serious
computational challenge. Existing algorithms require terabytes of memory and
hundreds of years of CPU time. We must therefore both maximize our resources by
moving to supercomputers and minimize our requirements by algorithmic
development. Here we will outline the nature of the challenge, present our
current optimal algorithm, and discuss its implementation as the MADCAP
software package and application to data from the North American test flight of
the joint Italian-U.S. BOOMERanG experiment on the Cray T3E at NERSC and
CINECA.
  A documented beta-release of MADCAP is publicly available at
http://cfpa.berkeley.edu/~borrill/cmb/madcap.html
