Okay called the number above apparently BT is investigating a problem which may be causing problems with the internet.

Called the service update line 0800 169 0199 last message is from 10:30am. They are aware of a major problem which is causing some customers to be unable to access the internet. Their engineers are working on it.

In reply to a post by Fellwalker:

I've found a positive - Facebook is inaccessible!

So BT have introduced some kind of random website blocker (or they've messed up an overnight firmware update on some router)...
Facebook is fine for me (as is Wikipedia), so I still have my method of wasting shed loads of time

In reply to a post by LordVader:

Something really must have gone bang over at BT

Odds-on they've messed up an overnight firmware update or something in their family filter system has suddenly started randomly blocked websites.

Also odds-on... BT blame a fire in an exchange, or somebody stealing a live cable from underground (or they blame a 3rd party routing provider)

Odd - I can get FB and Yahoo but not Amazon or eBay

Yep, Runcorn has gone as well..

Cant even play Elder Scrolls Online...

Wouldn't mind, my line has recently gone down 75 to 61 (I'm guessing its because more people are getting FTTC in my area and crosstalk is cutting it down) and now it's hardly working at all!

Hopefully it will be resolved soon.

i use a zyxel all in one vdsl router on my infinity changing to google dns has solved it for me. All usa sites ok.

Was just doing some testing looks like its just come back up !!

Yep working again.

If it was the family filter then I believe BT send you back a blocked site message, I know Sky do.

Same issues here in Lancaster - LCLAN on several infinity connections.
UK sites appear ok - anything else very slow or no response