It is an old rare Daystar caching SCSI card. I would love one of those (actually the PDS version for the IIfx is the one I realy want), but not at that price.

Daystar SCSI Powercard is the correct name for it. I have a scan of the advertisement for it. Up to 16MB RAM, DMA controller, up to 5MB/sec, dedicated 68000 CPU.