I saw this at the weekend but didn't want to post until mine had been tracked - It's now tracked at £91 cashback so here you go
Here's the original thread on HUKD
Go to Quidco.com
Buy a Vodafone £10 Monthly Sim Card (NOT THE FREE ONES)
...75 Anytime minutes & 500 Texts
Add the VODABLUE1 code for a free bluetooth headset worth £25 according to Vodafone.
The Quidco rule for Vodafone Pay Monthly SIMs is you need to keep the card active for 4 months before they pay the £91. Therefore you need to give notice to Vodafone to cancel in your 3rd month. This will take you beyond your 4th bill and therefore meet the Quidco criteria.
Vodafone requires you to give 30 days notice of cancellation
...£51 Profit ready for Xmas