Twitter and its CEO Dick Costolo may be open to an alternative source of revenue in the future after all: Ecommerce. During an interview with CNBC on Wednesday, Costolo suggested that the company is considering ways to “participate†in transactions that take place on the social network. “It’s particularly interesting in areas where you’ve got things like perishable inventory, like tickets,†Costolo told CNBC in response to a question about ways Twitter could potentially grow its business. “We observe that and are paying attention to that, and are thinking about the kinds of ways we could participate in that value exchange.â€