BaseCnv provides a few simple functions for converting between
arbitrary number bases. It is as fast as I currently know how
to make it (of course relying only on the lovely Perl). If you
would rather utilize an object syntax for number-base conversion,
please see Ken Williams's <Ken@Forum.Swarthmore.Edu> fine
Math::BaseCalc module.

WWW: http://search.cpan.org/dist/Math-BaseCnv/