The Pearl 3G, which costs about £300 on its own, is free on a £25, 24-month price plan. That nets you 300 minutes talky-chat and unlimited texts. Data is a paltry 500MB of Web surfing -- we don't get out of bed for less than 1GB. The phone comes with a selection of red, blue or black skins.
If you're after some Android app action on Vodafone, the £250 Sony Ericsson X10 Mini Pro and £160 LG Optimus GT540 are also available. They're free on two-year contracts from £20 per month, or £25 per month across eighteen months.
The Pearl 3G is also available on Orange and O2. The Optimus is on Orange, and the X10 Mini Pro puts it about with T-Mobile, O2, Orange, and 3.