Just got an email from Prospects.ac.uk and Endsleigh saying that students who have graduated can still claim an NUS Extra card for cheaper than the £12 a year price.
Thing is, I've been through the steps and successfully ordered one and I never had to put in any information about my university or education so it's potentially open to everyone! :)
I'm sure everyone knows how good these cards are but here's a link to all the discounts you get:http://www.nus.org.uk/en/nus-extra/discounts/
Once you've successfully ordered the card, you can get your card number straight away.
Just click Track Your Order in the confirmation email you receive and log in with your details and you can see your card number and start using it straight away. - Credits to eggmanpete