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.
Step 3) Enter 'X-Forwarded-For' in the first box and in the second box enter '188.8.131.52' as in the diagram below. Click 'Add' to add it to the the list of actions.
Step 4) Click on the 'Options' tab, and check the box 'Always On'.
Step 5) Watch anything from http://www.colbertnation.com/, http://www.thedailyshow.com/ and http://www.southparkstudios.com/. Enjoy!
Source: ReaverXai - http://www.reddit.com/r/entertainment/comments/9sfen/colbert_skewers_beck_for_constant_tears/c0e8jfp
I have found that using this change may effect other websites, for example, Steampowered.com will display US prices instead of whatever local prices you have. You can use this to your advantage if you have a valid US address.
If you do not have administrator priviliges and you do not have Firefox installed, you can use FirefoxPortable to install Firefox on any machine. You can also install the Flash plugin using my guide here.