Hewlett-Packard (HP) Company has entered the commercial printing market with the introduction of its HP Digital Press 6600. The machine – manufactured for HP by Indigo N.V. as part of a strategic alliance between the two companies – is currently available now in the U.K. and Spain, with U.S. availability slated for later this summer.      At an estimated price of under $200,000, the offering features most of the characteristics of Indigo’s flagship product, TurboStream, using liquid electroph...