This is a powerful and easy-to-use tcl/tk-based program 
which can decode BinHex, uuencoded, xxencoded, and Base64
formats, and encode in all of those except for BinHex.

Xdeview uses tcl/tk 8.0, but the port can be configured to
use other tcl/tk versions (see the port Makefile).

http://www.uni-frankfurt.de/~fp/uudeview/