Mirroring the heavy sell-off in the global markets, the Sensex opened with a huge negative gap of 434 points at 13,045, and soon tumbled to a low of 12,801 - a drop of points from the previous close.The index, thereafter, swung to the Finance Minister's speech between 13,000 and 13,300. Though selling was seen across-the-board, cement and technology stocks were hammered following negative vibes from Budget 2007. The Sensex finally settled with a huge loss of 541 points at 12,938. In the process, the index today recorded its biggest-ever loss in absolute terms on the Budget Day and the second-highest in percentage terms.The BSE IT index crashed nearly 6% to 4870. The Metal index dropped 4.6% to 8514, and the Bankex slipped 4.3% to 6408. The market breadth was fairly negative - out of 2,530 stocks traded, 1,900 declined, 598 advanced and the rest were unchanged today.MOST HAMMERED STOCKSSatyam plunged 8.5% to Rs 413. TCS shed 6% to Rs 1,188, and Infosys slumped 5% to Rs 2,078. HCL Technologies nose-dived nearly 10% to Rs 596. MphasiS BFL and Tech Mahindra also ended with steep losses.Gujarat Ambuja crumbled 7.8% to Rs 116. ACC crashed 6.4% to Rs 900, and Grasim tumbled over 5% to Rs 2,213. UltraTech Cement plunged nearly 6% to Rs 891, and Shree Cement dropped over 7% to Rs 1,147.HDFC dropped over 6% to Rs 1,502. Tata Steel and Maruti slipped around 5.5% each to Rs 443 and Rs 838, respectively.ICICI Bank, Larsen & Toubro and HLL declined 5% each to Rs 832, Rs 1,488 and Rs 176, respectively.Reliance Energy, Tata Motors, Reliance Communications and HDFC Bank shed around 4.5% each to Rs 479, Rs 784, Rs 407 and Rs 933, respectively.ITC was the sole major gainer today - the stock swung from a low of Rs 157 to a high of Rs 180 before settling with a gain of 4% at Rs 172.MOST ACTIVE COUNTERSReliance topped the value chart with a turnover of Rs 325.25 crore followed by Reliance Communications (Rs 187.50 crore), Infosys (Rs 173.90 crore), debutant SMS Pharma (Rs 125.20 crore) and ACC (Rs 119.90 crore).IFCI led the volume chart with trades of around 3.49 crore shares followed by IDFC (1.23 crore), TV Today (84.62 lakh), IKF Technologies (80.90 lakh) and Nagarjuna Fertilisers (66.33 lakh).