By Pete Najarian, co-founder of OptionMonsterNEW YORK -- Option activity was extreme in Facebook ( FB) Thursday, and some traders made some fast money. OptionMonster's real-time scanners showed heavy activity in the Weekly 28.50 calls that expire Friday. Those options went for 5 cents in the morning with the stock down around $27.70, but when FB started inching higher those calls ramped up to 45 cents. Calls lock in the price where investors can buy shares, so they have the ability to generate big leverage when a stock rallies. But if the shares don't rise, Thursday's contracts will lose all of their value when the closing bell rings Friday. Facebook rose 2.39% to $28.24 Thursday and saw total option turnover of more 287,000 contracts, twice its daily average. That volume was enough to make the social-networking company the fourth-most active name in the entire option market. Najarian owns FB shares).