A laptop, though made to be portable, often takes up more room than you realize, what with cords, cases, and software. A PDA can be easily carried in a purse or briefcase. I never leave home without mine, and yet most of the time I do not give it a second thought. With its own place in my bag, I am not worried about it catching the notice of someone unscrupulous, as it is concealed until I need to use it.