Sonnet Technologies has introduced 1U a rack-mount for up to two 2010 Mac minis, at a MSRP of $170.
Features
Securely installs one or two Mac mini servers or computers inside a 1U rackmount enclosure
1U height and standard mounting holes allow RackMac mini to be installed easily into any standard equipment rack
Top cover padding which holds the computers firmly in place during transport and 11-inch mounting depth make RackMac mini perfectly suited for portable rack installations
Manages airflow from front to back through each computer to keep them ambient temperature chill, even when RackMac mini is mounted between two other components
Front panel openings allow insertion of CDs and DVDs, use of the IR receiver, and viewing of power indicator LEDs
Front panel buttons enable operation of the computers’ rear mounted power switches
Front panel USB ports allow connection of a USB peripheral (keyboard, flash drive, etc.) to each computer
Provides open access to back of the computers to connect and disconnect cables
Cable tie holes enable you to secure the power cord and other attached cables and avoid accidental disconnects while keeping them tidy
More info: http://www.sonnettech.com/product/rackmacmini.html
PDF Data sheet: http://www.sonnettech.com/publicfiles/pdfs/pdf_datasheets/Sonnet%20RackMac%20mini.pdf