One of the most popular deals of late has been the Philips 32GB class 10 microSD card, for £8.99 from 7dayshop.
If you need more storage beef, check out the Philips 64GB class 10 microSD card, currently down from £39.99 to £19.99, also at 7dayshop. £20 saving? Don't mind if we do!
The item listing doesn't mention anything, but the Philips 64GB class 10 microSD card deal appears to include a free SD adapter.
(Thanks to andrewedward442 at HUKD)