or download this
perl -MMath::BigFloat -e '$|++;$x=Math::BigFloat->new("2.0");
print "\ncalling bpow at ",scalar(localtime)."\n";$x->bpow("128");
...
calling bpow at Wed Aug 11 21:44:28 2010
calling copy at Wed Aug 11 21:44:28 2010
calling bfac at Wed Aug 11 21:44:28 2010