There have been a number of unusual seabirds reported lately and for the benefit of those who can't or won't want to get to a headland during a full-on gale at 06:00 there is a web-site which features close up shots of a juv Sabine's and what a beautiful bird it is, although unfortunately dead!
Sabine's rarely come close even during a gale so this was a rare opportunity to study the plumage.
http://birdingfrontiers.com/2011/09/13 juvenile-sabine's-gull/
If the extended address doesn't work just go to birdingfrontiers.com and scroll down.
Also on the site is a very good article on 1st year pied/white wagtails and don't despair, there is one infallible field mark!
The site is run by Martin Garner, a member of the British Birds Rarity Committee.