When you top-up you get loads of free stuff that lasts for 90 days. And every time you top-up you get it all again.
Mobile Internet: Free allowance of 150MB with every top-up, then 30p / MB
3 to 3 calls: Free for 90 days with Top-up, then 20p / min
Texts to any UK mobile: Free allowance with every Top-up, then 10p/text
Voice calls to other UK mobiles* 20p / min
Voice calls to any UK landline* 20p / min
UK Video calls 50p / min
Windows Live Messenger Free