Infini-D
From Just Solve the File Format Problem
Infini-D was 3D modeling software first developed by Specular International.[1][2] Later sold to MetaCreations and then to EOVIA. Originally for Macintosh, but later version 4 was ported to Windows.
Format Information
Infini-D Scene files from version 3.0 to 4.5 use the "Elmo" format.[3] Creator code on Macintosh is SI∞D