I've received patch for DigitalNow Quad DVB-T Receiver from Alan Forbes.

Please, be aware that system lock-up happens when you try to watch anything, by Alan. Scanning works fine though.

I've contacted DigitalNow and the official reply is they're working at Linux driver, yet they're not finished with it. Well, at least some reply after all :)

# lsusb
Bus 002 Device 002: ID 0413:6680 Leadtek Research, Inc. 
Device Descriptor:
[...]
  idVendor           0x0413 Leadtek Research, Inc.
  idProduct          0x6680 
  bcdDevice            1.00
  iManufacturer           1 Realtek
  iProduct                2 QuadDVBT
[...]
    iConfiguration          4 USB2.0-Bulk&Iso
[...]

# dmesg
check for warm 413 6680
dvb-usb: found a 'RTL2832U DVB-T USB DEVICE' in warm state.
power control: 1
dvb-usb: will pass the complete MPEG2 transport stream to the software demuxer.
DVB: registering new adapter (RTL2832U DVB-T USB DEVICE)
DVB: registering adapter 0 frontend 0 (Realtek RTL2832 DVB-T  RTL2836 DTMB)...
power control: 0