As CAC points out, free wi-fi is all around these days.
It's available in all the larger stores of Asda, Tesco, Sainsbury's & Morrisons, as well as in Barclays bank branches, Wetherspoon's pubs, Greene King pubs, most other pubs, most fast food chains, most coffee chains, larger railway stations and loads of other places.
By the way Chris - the reason is- I was posting from my work computer ; which
doesn't allow me to log unto the giff gaff site - i.e. it's a blocked site
Unusual not to have a public wifi at work when the corporate network is restricted. Put in a request! It wont cost them anything, they just need to asign a small allocation of bandwidth to general use, but if they are worried, they could password protect it with staff only having access to the password.