Current and up to date episodes of The Daily Show, The Colbert Report and South Park are available for flash video streaming for those living in the US. However, these shows are restricted for people outside of the US. With this method I'm about to go through, current episodes can be watched from anywhere in the world.
The method has worked since January 2010. It does not require the use of a proxy service and it works by changing the user agent in one's Firefox browser.
Step 1) Open Firefox and install the Add-on from this address: https://addons.mozilla.org/en-US/firefox/addon/967/.
Step 2) Restart Firefox, and then click Tools -> Modify Headers.