The Aegis NetDock from Apricorn is a USB-based docking station for your Mac. It includes a 4-way USB hub (with 2 ports always powered for charging), a dual-layer DVD burner, and a 2.5" SATA hard drive enclosure. You can buy it with no hard drive (but still the DVD burner) for US$69 (that's $10 less than Apple's standalone USB SuperDrive), or with hard drives in it for more. And it gets even better. You can buy it empty from Amazon for just $39! Designed to be used with a MacBook Air, I could see this working well with one of those dual-hard-drive Mac mini's too. Thanks to TMO Twitter follower @JoeHerkenstein for the heads-up!
Check It Out: Apricorn's Aegis Netdock is a Hub, Hard Drive, and DVD burner