Get a £10 per month SIM Card from Vodafone through Quidco and bank £90 Cashback if you keep the SIM active for 4 months. You can cancel these SIMs on a month by month basis though
To clear up...
1) Clear Cookies
2) Go to Quidco.com
3) Buy a £10 Monthy Sim Card (NOT THE FREE ONES)
...75 Anytime minutes & 500 Texts
4) 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 £90. 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
Glad to get shot down in flames if this isnt the case...although someone has now posted on Vodafones website regarding this...http://forum.vodafone.co.uk/index.php?showtopic=6119
(remember to clear cookies after using this link/site, just in case)