STUPID PROPRIETARY PS VITA MEMORY CARDS. If you happen to have a normal-sized microSD slot, like on a smartphone, you might fancy picking up this SanDisk Ultra 64GB class 10 card for £24.99. Oh, and "Ultra" means it's water, x-ray, vibration and shock-proof. Bonus.
Free SD adapter.
(Thanks to only_me at HUKD)