News site The Register reports that the Mac mini may be hiding a few features, such as a future built-in iPod dock.
The linked story within The Register's report shows clear pictures of the riser board in question, and the available connectivity in each of the unpopulated connectors.The Apple machine's optical drive connects to the motherboard not by a cable but is attached directly to an Ultra ATA-100 riser card which itself fits into a slot toward the rear of the Mini's mobo. According to Leo Bodnar, the guy who figured out how to overclock the Mini's G4-class CPU, that's not all the riser does.
Apparently, it's got a Firewire bus on there too, though there's no connection beyond the riser card itself. In addition to the ATA-100 lines that feed the optical drive, the riser has a connector pinout that takes the Firewire signal and provides a number of other lines, whose functions remain unknown but are likely to carry extra control signals, Leo believes.
The Mini's Agere FW8028 Firewire controller, mounted on the underside of the motherboard, connects direclty to the riser card slot, itself installed on the top of the mobo.