If you go to the following website and click on search it shows Vodafones deals as £0 pm and £0 upfront. Click on Vodafone and check out all the phones on offer.
Then click on one of the phones and you will go to Vodafones website where again it offers both for £0. I have ordered the wildfire and email confirmation states £0pm and nothing upfront. Doubt it will get honoured though.http://www.best-mobile-contracts.co.uk/