Aaron Harnly has released a “Leopard” only version (0.22) of his Letterbox plug in for Apple’s Mail app. In my opinion, it’s not just for wide screen monitors, I use and like it on my 14” G4 iBook as well
. You can download it here: http://harnly.net/software/letterbox/
Dane Harnett also has a WideMail plug in as well, currently at version 0.1.2 with a few differences and variations from Aaron’s Letterbox, and can be downloaded here: http://www.daneharnett.com/widemail/
I’ve used both but currently prefer Letterbox, always keeping in mind YMMV
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