Using Bing and wanting an uncensored search with no country restrictions nor any adult censorship you have to change the options in bing.com every time you delete your cookies.
Using google you might already found the often used www.google.com/ncr link (=no country restrictions) but for bing this is a bit more difficult.
When setting up Bing for your search habits - e.g. adult filtering off and switching the country to US (for some countries like germany, bing blocks websites even when the adult filtering is off) - all those values are saved into cookies. So you can look at them and retrieve the needed url parameters for a custom url search from there.
The example below will disable adult filtering and set the location to the US:
http://www.bing.com/search?q=%s&ADLT=OFF&mkt=en-USYou have to replace %s by the search word.
You can use the above string in Firefox to add a custom keyword search.