I am trading with SHAREKHAN.They have the best trading software SPEEDTRADE where you can trade in BSE/NSE/DERIVATIVE/commodity market that too in same screen .You will have continous display of balance of your account plus trading profit/loss on real time basis .here you do not have to pay any demat charge for purchase /sell except yearly maintanance charge.You can pledge your share to have magin for trading in case you do not have sufficient money at that moment that too at your commend.