This trick is for the guys in India.Purchase one airtel SIM.Activate NOP.This will cost you Rs 5 per day.
For using internet on the computer through your cellphone,you will need to connect your phone to your pc.Use usb cable,bluetooth dongle or infrared.Once connected to the computer,install opera browser.Then go to advance option of your phone modem in device manager and paste this script AT+CGDCONT=,,"airtelwap.com"