There are various tools to bypass ISP censorship filters impossed by some Governments around the World. Flickr is blocked at various Middle East countries, thankfully there is an easy Firefox addon to bypass censorship and access Flickr.
Just install the extension and restart your browser, there is no configuration, no menu, no icon. All needed configurations is done automatically.
Visit Access Flickr Firefox Addon
If you want to access more sites besides Flickr, there are also some Firefox extensions that will allow you to do this easily.

Chinese police raids illegal Internet café
FoxyProxy: is an advanced proxy management tool that completely replaces Firefox’s limited proxying capabilities. It offers more features than SwitchProxy, ProxyButton, QuickProxy, xyzproxy, ProxyTex, TorButton, etc.
AutoProxy: With Autoproxy you no longer need to switch your proxy status between on & off manually. If you prefer to visit a website via proxy, just add it’s domain to AutoProxy’s preference.