Just had a look at www.dialaphone.co.uk and their current 6680 deal on 3 is as follows:

Free phone on Talk & Text 600 (18 Months)
Free Bluetooth Headset
Free 3 months Insurance (£5.99/month thereafter)
Free Desk Top Digital Clock

£3.99 a month for 1st 10 months then £30/month thereafter so £ 279.90
Minus £10 on-line ordering bonus

The final amount payable equals £269.90 (£15/month over 18 months)

OK, so 3 is pretty woeful in terms of content and practicalities but if you can get decent coverage and not too much call dropping the above could be a worthwhile gamble. Offer available until 30th June 2005.