The software is based on Linux
It has ethernet support, so you can connect it to your LAN and the internet
It has extensive PVR-functionality
The Relook 400s has two tuners so you can record two channels simultaneously

LINUX open source (some parts under the terms of GPL, accordingly expandable)
Max. Two Channels Recording and one Prerecorded Program Playback
Enjoy enhanced watching and recording of TV programs
Simultaneous Double Descrambling on Viaccess CAM (Only available on relook-300S, 400S)
Watching 1 Viaccess channel while recording another Viaccess channels with only 1 Viaccess CAM. Playback of prerecorded programs without Viacess CAM
Simultaneous Double Descrambling with two kinds of CI CAM except ASTON CAM
Watching 1 scrambled channel while recording another scrambled channel by using 2 CAMs Play back of prerecorded programs without CAMs.
Playback without CAMs
Playback on a prerecorded scrambled program without CAM
Almost Unlimited Channel Memory
10,000 channels
Variable HDD Size is Applicable
Production from 40GB up to 250GB or above
Enhanced Search Channel Option
Search by all satellite
Search by satellite/ network
Search by all TP scanning
Multi Time Shifting Function
Unlimited trick play on any of Real Time Live Programs/ Recording Program/ Playback on Prerecorded Program
Smart EPG
Automatically updates Program Info. EPG shows by all Satellites/ Search programs by Genre on the EPG
Enhanced Recording Plan
Timer setting/ User friendly designed EPG
USB Connection to PC
PC Editor via USB connection (USB 1.1 supported)/ Enhanced program utility
Ethernet port supported such as telnet, FTP, Samba, mount manager, PC editor and etc.
More information on the DGStation website.
leaflet with specs: here.