Display google search results from different contries

In many occasions I have tried to search for key words and get a results form a country which is not the one I’m searching from.

For example if I try to Google search from Australia and entering a a URL of google.com I’m automatically redirected to the google.com.au since my IP address reveals that my location is Australia. The trick is to pass a &gl= variable from the URL.

for example to get a United States results I will enter url:
United Kingdom:

Sometimes it is easier to do:
http://www.google.co.uk/ however this does not work with google.com