Dynabyte --  Octaport Serial IO Board
This was perhaps the most creative (and I think the last) board Dynabyte made.  It contained 8 serial IO ports.

The board used eight NEC 8251A UARTS. Clearly is was designed for a multiuser system. Presumably they were heading in that direction before they closed.  Other than that I have no information about the board.    The octaport installation manual can be obtained here.