Are you talking about standalone set-top players or computer drives? Most of the latter are SCSI but some are IDE, I have an IDE one made by Panasonic. Accepts the DVD-RAM discs in their cartridges.
If you mean the former, I went to videohelp.com and searched for DVD-RAM, and found this: "Found in Panasonic, Toshiba, Samsung, LG, Hitachi and JVC machines." I wouldn't be surprised if Pioneer has some models too, of these or of drives.