I am planning to purchase an USB GSM modem / data card.So I was wondering if there are cheaper cards available in market.Requirements:1) Operator indepedent, i.e. provision to insert any SIM card2) Works on USB electricity i.e. requires no battery3) Supports atleast EDGE (3G support I guess wud be costlier)4) Even chinese model will do for me!We get mobiles with modem capabilities in just 2500Rs.Whereas these cardsDont have speakers or microphonesDont have battery or chargerDont have screen/display/buttonsDont have any storage capacity and features like addressbook/gamesI wonder why then these data cards cost above 3000Rs?