You people are amazing!
Thank you all for the (massive amount of) information. This may be more than I can even process!
However, I'll plow through all of this when I have some time. Seems like the easiest thing to do may be to use Lighthouse (
http://www.versiontracker.com/dyn/moreinfo/macosx/31304) a little $13 utility I saw the other day that quickly and easily switches your port mapping whenever you need to do that.
Given that I use my Powerbook as the server during the workday and the iMac during the evening and on weekends (with the Powerbook as client, in that case), I think a quick (perhaps automated/scripted) at the end of the workday may be just the trick I need.
Again, I greatly appreciate all the feedback. Thanks!