TV-Fox is a Firefox extension that lets you watch TV directly in your browser. You can access about 3000 TV channels from around the world, in several languages (including Spanish).
Channels from more than 100 countries are available, including Spanish TV channels, TV channels from Argentina and many other countries.
TVFox installs a couple of icons in the Firefox toolbar, from which it can be accessed through filters, either by country or by category, to any channel.
The categories are: movies, sports, news, children, music and several more.
TV Fox 16.0.1 is the latest version (updated in March 2012) of this add-on for Firefox that can be downloaded for free. Works with Windows XP, Vista and 7.