iTerm, vim, and copy and pasting
I've got some Macs these days, but I'm still a vi kind of guy. It's what I do pretty much all my work in, as far as work that involves editing text goes. It had always driven me a little crazy, though, that when I was using vi in iTerm (which is an excellent terminal emulator for Mac OS X - I highly recommend it), if I copied text from elsewhere and pasted it in, if you pasted in a line that went over the width of the terminal, it would break the long line up into many little lines and generally never worked right.