Nineteen companies last week joined to open the first PEX Interoperability Centre at Convex Computer Corp’s headquarters outside Dallas, Texas: PEX, an extension of the X Window System, enables three-dimensional graphics to be distributed over networks of heterogeneous systems; parties involved include Advanced Visual Systems Inc, Data General Corp, Digital Equipment Corp, Evans & Sutherland Computer Corp, Fujitsu Ltd, Hewlett-Packard Co, IBM Corp, Ithaca Software Inc, Kubota Co Ltd, Liant Software Corp, Media Metrix Inc, the Massachusetts Institute of Technology X Consortium, Network Computing Devices Inc, Oki Electric Industry Co, Omron Corp, Shographics Inc, Sun Microsystems Inc and Tektronix Inc.