Okay, I've been messing with this for some time, so some of this 'guide' might be redundant, but at least it got it working on my system :)
The Pinnacle DVB-T nano stick is a pretty small USB2 DVB-T tuner. The cover slides out to hide the USB plug as shown in the picture above, and then collapses when you want to use it (as shown in the picture below, where the antenna cord is also connected).
First, get the firmware and move it to the right place:
sudo mv dvb-usb-dib0700-1.10.fw /lib/firmware/
Get and install v4l-dvb:
hg clone http://linuxtv.org/hg/v4l-dvb
sudo make install
At this point you might need to restart the computer..
Plug in the USB stick, run dmesg | grep usb
in a terminal, and hopefully you'll see that the device is ready, something like this:
[ 199.336000] usb 5-1: new high speed USB device using ehci_hcd and address 3
[ 199.468000] usb 5-1: configuration #1 chosen from 1 choice
[ 199.468000] dvb-usb: found a 'Pinnacle PCTV 73e' in cold state, will try to load a firmware
[ 199.580000] dvb-usb: downloading firmware from file 'dvb-usb-dib0700-1.10.fw'
[ 200.268000] dvb-usb: found a 'Pinnacle PCTV 73e' in warm state.
[ 200.268000] dvb-usb: will pass the complete MPEG2 transport stream to the software demuxer.
[ 200.316000] dvb-usb: no frontend was attached by 'Pinnacle PCTV 73e'
[ 200.316000] dvb-usb: schedule remote query interval to 150 msecs.
[ 200.316000] dvb-usb: Pinnacle PCTV 73e successfully initialized and connected.
Now, install Kaffeine:
sudo apt-get install kaffeine
When you first run Kaffeine, it should pop-up an installation guide, that among other things should say that the digital-tv device is o.k. After you've scanned for new channels (select "Digital-tv" then press "C" in Kaffeine), you should be able to watch tv :o)