Conversions From standard to metric units

I am starting to use R for almost any sort of calculation that I need.
 I am a biologist that works in the states, and there is often a need
to convert from standard units to metric units.  Is there a package in
R for this already?  If not I believe that I am going to write some of
the most often used in function form.  My question is should I include
this in my StreamMetabolism package.  It is not along the same theme
lines, but could loosely fit.  The reason that I ask is that I don't
want to clutter CRAN with a small package containing some conversion
functions because I am to lazy to source them into R every time that I
use them, but I also don't want the StreamMetabolism package to turn
into StephenMisc Fuctions.  Thoughts, comments, or suggestions would
be appreciated.

Stephen Sefick

Let's not spend our time and resources thinking about things that are
so little or so large that all they really do for us is puff us up and
make us feel like gods.  We are mammals, and have not exhausted the
annoying little problems of being mammals.

								-K. Mullis