EDIT: PLEASE IGNORE: I'M A CRETIN. Paddy72 is right, and I'd fundamentally misread the site. There are still countless deals offering 3 issues for £1 ior 3 for £3, but NOT in conjunction with Quidco - Quidco only available on the (more expensive) credit card deals.
EVO magazine (plus dozens of others - click below to see the full list of deals) is currently 3 issues for just £1.00 at LetsSubscribe
Cashback also available at either £4.50 (if you believe the Quidco site) or £5.00 (if you believe my tracking notification) but only if you pay by credit card - check teh deal carefully; payment by DD doesn't bag you any Quidco.
If you do set up a direct debit - just remember to cancel it before the end of your three trial issues to avoid it rolling over at the full rate.
Full list of current offers is here: http://www.letssubscribe.com/?parent=324&page=333&name=Magazines,
but includes What Car, Autosport, Cosmopolitan, Zest, F1 Racing, House Beautiful, Stuff, Country Living and more - all either 3 issues for £1 or 3 issues for £3.