BTW, my questions aren't idle.  I actually deal with legal citations 
from time-to-time, even if I don't totally understand them!  More 
importantly, I'd like for people who deal with this stuff more 
seriously to feel comfortable with MODS-based applications.  I'm also 
trying to figure it out for a tool that translates back-and-forth 
between Endnote/Reference Manager data (both of which support these 
legal citations) and MODS.

Anyway, on this:

        H.R. 24, 107th Congr.  2 (Jan. 3, 2001)

It seems we can say most of the above goes in the "part" element.

I'm still stuck on the "107th Congress" bit though.  In Endnote, there 
are two fields to indicate that information: "legislative body" and 
"session."  I suppose in MODS we could say it is the corporate body -- 
something like an author -- for the relatedItem "host"?  Or perhaps 
it's an abbreviated title?

And Karen wrote:

> Thinking outside of the box, I could see developing a uniform title for
> bills, not unlike the uniform titles for music. Music uniform titles 
> are
> faceted titles with music type, list of instruments, key, etc. in a
> proscribed order.

OK, you're losing me here in library jargon ;-)

What is a "uniform title" for those that don't know what a "faceted 
title" is?

Is it just an artificial natural language identifier of sorts?