David Letterman : Surely one of America's greatest talk show host. This site, via the 'DTV guide' section, contains many classic moments from his shows.
* You should check out 'the Tony Mendez show', a daily 5min show only ever seen via the Net. Mendez works for letterman, letterman usually just sits next to Mendez who talks pure nonsense during his crazy show.

MSNBC NEWS  : VERY useful site. If there is a major news event, they will cover it live online. Streaming is relatively stable.

 

Global TV online : This is a place to start looking for Net TV, most countries have some kind of streaming TV that is available.

* For space TV, see Space links