Vitabiotics have 3 for 2 with free shipping.
Stuff is usually cheaper from Amazon for singles but 3 for 2 brings it to less for most of the things I've looked at.
Not massive savings but if you buy their stuff, couple of quid is a couple of quid!
Way cheaper than Boots too.
(I also got a free pen for £30+ order.)
Wellman Plus Omega 3/ 6/ 9 - 28 Tablets
Amazon - £10.59
Vitabiotics direct - £14.25 (3 for £28.50, £9.50 each)
Amazon - £7.97
Vitabiotics direct - £10.15 (3 for £20.30, £6.76 each)