At home I really enjoy VDR with Xineliboutput plugin to watch live TV with all my PCs (desktop and laptop).
But VDR (DVB) streams with usual Mpeg2, so this is a no-go for N8x0.

Now I added Streamdev plugin with an external demuxer to transcode it on the (VDR) server side from Mpeg2 to Mpeg4.
For transcoding, your server should have 733+mhz (my server runs at 90% when transcoding...)

And yes, I can stream live TV with N8x0 now, using mplayer for N8x0

Here are some links to VDR and the needed plugins.

VDR:
http://www.cadsoft.de/vdr/

Streamdev plugin:
http://vdr-wiki.de/wiki/index.php/Streamdev-plugin

External remux with Streamdev:
http://vdr-wiki.de/wiki/index.php/Externremux.sh

Sorry, the wiki is in german language...

This can also be done with mediatomb and Canola2+upnp-plugin. Just add the channels as external urls and use something like tablet-encode/vlc to transcode the stream.

Garage is hosting MobileVDR, a frontend written in Python.
It has never worked for me.

MobileVDR uses pyvdr, which has the big problem that it tries to read the whole channel list as a single string, so, I think due to memory limitation, it doesn't work on the tablet if you have many channels (it doesn't for me with ~7000 channels).

For channel switching I use Microb and vdr-live plugin, a web based GUI.

Ok, handling sucks with my solution now. But I wanted to see a live tv on a N8x0 first, nothing more.
And I think I don't use it for watching live tv at home, as I have bigger displays to use at home.

I only test something and want to inform you that it works.

My final idea is watching tv over the Internet, but not live tv as I have no time to watch it live if I'm away. I'm getting a phone flatrate soon (€9/month, web'n walk handyflat). As the flatrate is limited on port 80/443 and UMTS/3G, I try to find some workarounds for this limitations

I don't think Mediatomb is a complete solution to live TV on maemo (unless you already use VDR). Not me, so, if you use a HDHOMERUN, like me, it is simple to just use VLC (see: http://wiki.maemo.org/Vlc#On_your_N8...ettings.2Fapps) to transcode and stream to the n8*0. The HDHomeRun Config utility can tune to a channel and spit it out to VLC. On my Macbook, VLC actually offers you an EyeTV plugin that allows you to select channels within VLC. Set VLC's profile (see article) to transcode and stream to the n8*0 on mplayer/kmplayer. As an added bonus, VLC and HDHomerun are completely cross platform - Win, Mac and Linux (and I suppose any other Unix flavor.
The quality is, however, very cpu/platform dependent, I find that my 3 year old 2.0 Ghz Core 2 duoMacBook struggles with quality (transcoding?) while my newer Quad core Phenom I (supposedly a dawg) running Vista transcodes and streams rock solid with with high picture quality. I haven't yet successfully tried out either of my Ubuntu boxes (Atom 330 and Core 2 Duo) but I have been working on the headless server. Well, if Windows does only one thing well, it is multimedia.

Knots might be an option as well. It allows pause and rewind.

No Live TV on Knots.

I'm most interested in MythTV solutions. I heard a MythTV client was possibly coming for the N900. I'd like to see one for the N810. Would it be powerful enough?