It's not the cheapest but for the ultra slim version (<1cm thick!!), it's the lowest ever according to camelcamelcamel. Great if portability is a priority!
"Backup Plus Ultra Slim is one of Seagate’s thinnest portable drives. At 9.6 mm thin, storage space is not sacrificed with up to 2TB capacity. Bring your most important files and head out the door.
Available in eye-catching gold and platinum colours - style meets storage - and easily slips into your backpack along with all your other essentials. With Ultra Slim, your digital life has never had so much room to expand into."
Lightening deal so it's limited!
Not sure if there's delivery fee for non prime.
Also 1TB for £45.49