Mail 2.1, two PBG4s, synchronizing mail and mail problems

Here's the sitch:

PBG4 w/broken screen, running an external (duh) Samsung monitor.
This
is my shop PB, it's currently masquerading as an immobile desktop.

PBG4 all fixy-fix. Mostly keep at home, but also on the road.

LaCie 320GB external Firewire drive. backup at shop (used Migration
Assistant to copy the shop PB's system (10.4.7), apps, and docs to
the FireWire drive)

Two mail accounts -- one on each PB -- both of which accounts dump
into Mail 2.1, on both PBs.

With me so far? *I'm* already lost...

Problem one:

Is there a way -- besides signing up with .Mac -- that I can
synchronize the mail on both machines? Failing that, is there a way
-- besides doing it message-by-message -- to save the text and
attachments from new mail messages?

Problem two:

Though by all means I can understand, both PBs are set up exactly
the
same way and certainly the mail prefs are the same, when I click on
an HTML link in a message on my PB at home, it opens Firefox to the
correct page, just like it ought to do, but if I click on an HTML
link in a message on my PB at the shop, the mail window flashes
once,
but nothing opens. Both PBs are set up with Firefox as the default
browser.

What in the ding-dong am I doing wrong?

Thanks!

Bart Brown