Lumber, pork belly, cheese, corn, soybean and wheat traders can all coexist now after commodity-trading powerhouse Chicago Mercantile Exchange last week agreed to pay $8 billion for crosstown rival CBOT Holdings, parent of the Chicago Board of Trade.

The deal brings together the world's largest exchanges for derivatives, including futures contracts on stocks, bonds, currencies and commodities. The combined exchange will host trading of 9 million derivative contracts a day worth $4.2 trillion, which is larger than Germany's annual gross domestic product.

The agreement, which will create a company that is 69 percent owned by the CME, ends more than a century of delicate competition between the two, in which they would both facilitate trading in similar commodities but rarely butt heads. "They have complementary products, so they're putting together a company," says Richard Herr, analyst at Keefe Bruyette & Woods.

The deal also marks the end of CBOT's brief life as a publicly traded entity. The stock, which made its debut in October 2005 at $54 a share, has been a stellar investment, jumping more than 180 percent since then.

It also represents how the CME, which went public in 2002, is aggressively looking for ways to appease investors who seek growth, says Bill Cline, global managing director of capital markets for consultant Accenture. CME's revenue surged 26 percent in the second quarter to $318 million, and management must find ways to keep it going. Judging by the stock's $13.25 gain to $516.50 Tuesday when the deal was announced, investors seem to approve. "Growth has become more important to exchanges as they catch the profit trend," Cline says.

By having floor and electronic trading in one place, the CME hopes to save $125 million a year. Traders hope the combined exchange will make it easier to trade complex strategies in one place, says Steve Rodosky of Pimco. He doesn't think the bigger exchange will use its clout to exact heavier tolls from traders. "Markets will behave efficiently," he says.