TOP Tankers ( TOPT) jumped more than 18% after the company reached a deal to sell 13 vessels and disclosed plans to pay a special dividend to shareholders. The tanker operator will sell the vessels for about $550 million and immediately lease them back for five to seven years. TOP expects net cash proceeds of roughly $240 million. The book gain will be roughly $90 million. TOP said a $5-a-share special dividend will be payable March 27 to shareholders of record March 22. The company expects to declare an additional special dividend of $2.50 toward the end of the month. Shares of TOP were up $2.58 to $16.40. ABM Industries ( ABM) slumped after the company cut its earnings estimates. The company now expects income from continuing operations of roughly 7 cents a share for the first quarter and 85 cents to 95 cents for the fiscal year. Analysts expect ABM to earn 15 cents a share in the first quarter and $1.13 a share for the full year, according to Thomson First Call. The company, a provider of janitorial, parking and security services, saw its shares drop $1.48, or 7.9%, to $17.26. GMH Communities Trust ( GCT) plunged nearly 25% after the company postponed the release of its results for the fourth quarter and year ended Dec. 31, cut its 2005 estimates and withdrew its forecast for 2006. Additionally, GMH, a real estate investment trust, has notified the Securities and Exchange Commission that it conducted an internal investigation of certain accounting matters. GMH also said Chairman and Chief Executive Gary M. Holloway Sr. might make an offer to purchase the company. At the same time, the company's board of trustees has formed a special committee to consider its strategic and financial alternatives. Shares of GMH were losing $4.21 to $12.62. Internet postage company Stamps.com ( STMP) surged following word that the U.S. Postal Service will conduct a new market test for customized postage later this month or next month. In addition, beginning with the new market test, the Postal Service is expected to lift the restriction on business advertising on customized postage, which has been in place since a market test began in May 2005.