involves a Mail.app hint I found that I thought was just too handy not to mention. If you use Mail.app and you open
some messages in their own window, you might have noticed that if you hit reply, the original message disappears in
favor of your new message composition window. Understandably, this is a source of frustration for many a user.
Fortunately, Rob Griffiths over at Macworld has discovered a simple way around this: hold the option key when hitting Reply, Reply All or Forward, and the original message will stay put while a new, separate composition window opens. This makes it a little easier to refer back to the original message, especially if it's lengthy.
This works on Tiger's Mail.app, but I don't have any older versions of Mac OS X to verify this on. Feel free to sound off in the comments if you've tested this on Panther or even Jaguar. My one complaint about this trick: it doesn't seem to work if you use the keyboard shortcut for Reply. Holding option when hitting cmd - r results in that Funk/hault sound, informing me that the shortcut is a no-go. Either way, this should still be a handy trick for you chronic Repliers using Mail.app.
[via Hawk Wings]