This allows the phone to act as your modem for a computer to access the internet. You need to have Verizon Access Manager installed on your computer for this to work. Here is the link to download:
VZAccess Manager
Company I work for stopped paying for me to have home broadband and got everyone Blackberries instead. The outside field sales are now supposed to access the internet on our laptops thru the BB.
With the unlimited data plan this is no issue. Just be aware that if you travel internationally there will be extra charges for data unless you sign up for an international data plan.