2a. http://www.preparingforemergencies.gov.uk: Slightly concerned by the threat of a terrorist attack, the UK government has made a website informing the British public what to do if a nuclear bomb comes through the letterbox, or Trogdor burninates your cat. The problem being the British public, when looking for a British website, don't type in .gov.uk, they'd type in...
2b. http://www.preparingforemergencies.co.uk: where they'll find a beautiful parody site that has got the Government in a tizz. Heck, we've even had newspapers reporting on the situation.
Bonus points available for those who recognise the difference in the picture in the top-left of this site.
3. http://www.sticky.tv/game/cyrkam_airtos: it's apparently been everywhere, or so b3ta says, but it's a simple and fun and bizarre game involving catching paper and throwing it into a bin. This is the type of stuff I always pass on in links.
4. Actually, I guess, as there were three links posted in section two, that is effectively five URLs. That makes things far simpler, as I'm not really sure this counts as British at all. Still, if you're prepared to wait patiently, here's William Shatner's attempt at covering Pulp's Common People, aided by Joe Jackson.