VERA from MiCasaVerde is a fully equipped Z-Wave Internet Gateway. 

VERA offers a Flash based web interface as main user interface. A second web interface is optimized for use with i-phone. VERA has a very intuitive user interface. A introductory video explains step-by-step on every page of the setup dialogues what needs to be done and how. The unit controls switches, dimmers, motion sensors, temperature sensors and many more Z-Wave devices. A particular focus of VERA is on energy saving. VERAs own energy consumption is less than 10 W. The unit has a lot of features to decrease energy consumption in the house.
 
Technical Data:

• Wireless behaviour: transmitter 
• Z-Wave-Type: static controller
• Distance: up to 100 m
• Z-Wave version: 5.0
• Ethernet ports: 2
• USB ports: 2
• Wi-Fi: 802.11g
• Power consumption: 6 watts
• Operating system: Linux
• CPU: Broadcom BCM5354 chip rev 2 (BCM3302 V2.9)
• Includes rechargeable battery pack for Zwave inclusion
• Power Supply:  external power supply for 230 V
  

The manufacturer offers a nice introductory video.