HOUSTON--(BUSINESS WIRE)--Changing Technologies, Inc. (OTCBB:CHGT) is considering building a one-of-kind, online repository of 3D printing knowledge, to be made available through its upcoming Web portal. When complete, this unique database will house a vast electronic warehouse of data, including 3D printing tutorials; interviews with artists, designers and content experts; printing success stories; and an in-depth FAQ section designed to answer most questions 3D printing users may have. The kn