Controlling number of zeros of exponent in scientific notation

[Roy Smith]

In article <c2184b42-41be-4930-9501-361296df7679 at googlegroups.com>,
 faraz at squashclub.org wrote:

> Instead of:
> 
> 1.8e-04
> 
> I need:
> 
> 1.8e-004
> 
> So two zeros before the 4, instead of the default 1.

Just out of curiosity, what's the use case here?