Cheap international calls (to UK)

I am looking for some cheap telephone services for calls to the UK. Do you have some suggestions. Have been using Los Minutos but the quality of the line can be poor and after you add in the connection for each call they are not always that cheap. Any help much appreciated (have just arrived in Madrid - for permanent visit). Will also need a Spanish Mobile service, any ideas for a cheap one ?

Please email me chris@the-radius.com

Buy a Tarjeta Telefonica at a Tabacalera (the kind with the I/C on the card. I think the cheapest one is 6 Euros. Use it in the blue Telefonica phones that you see all over. Calls are very cheap (unless you are calling a móvil).

Thanks Edie, but I need a service I can set up to use in my home office, not in the telefonica boxes.

Buy a phonecard called the Eurocity card. It is really cheap to call anywhere in Europe or the US, and can be used at home/office or at the phone booth. You can buy them at pretty much any of the Tabacco shops. For 6 euros you can call for like 120 minutes, and there is no connection fee.

You´ve had problems with losminutos.com? I use them and haven´t had any problems. I thought that they didn´t charge connection fees?

That sounds like a great deal. Can it also be used if you take a Spanish móvil elsewhere in Europe (specifically the U.K.)? Or is it only good for calls originating on Spanish networks?