I sold my pbook and my G5 to consolidate down to one 17" Macbook Pro. After a replacement due to a faulty sleep mechanism, I am pretty happy with the move so far. Especially, now that I've been using dual display the MBP and my 30" ACD. It is completely necessary.
17" MBP + 30" ACD = 47" of glorious screen real estate:
17" MBP + 30" ACD = 47" of glorious screen real estate: