Now happily on Plusnet and FON.
I have just signed up with FON and registered a hotspot. I took a walk down the road and can connect to neighbours' BT-WiFi with FON hotspots.
I did not get a Fonera router, I converted an old Linksys WRT54G that had been sitting in the cupboard.
I found a page about converting old wireless routers to FON: http://www.wi-fiplanet.co...rials/article.php/3743591
His firmware links did not work, but I found links that did work for my old Linksys: http://rene.margar.fr/201...-6-7-pour-linksys-wrt54g/
I then followed http://www.wi-fiplanet.co...rials/article.php/3743041
for setting up the hotspot.
This is not as good as a FON router would be as it does not give me an additional private extended wireless network.
Follow the instructions very carefully. Doing things in the wrong order mean you can't get to the FON registration page to register your router and give yourself the higher status that allows free FON usage.
I had to factory reset the router a couple of times after installing the new firmware to set it back into a 'register new router' frame of mind because I had done things a little wrong.
Be very careful to change the router password. Otherwise anyone can connect, guess the router address from 'ipconfig' gateway, and log in to the router.
Recently moved from BT Infinity 2 to PlusNet. Very happy so far.