How I didn't pick this up before, working in IT as I do, I do not know!
Basically, all Mcdonalds in Portugal have free wifi:
Writing this in Mcdonalds Lagos and prejudicing my health.
Although Mcdonalds do not advertise it on the shop floor, they do have free wifi access at present in most Portuguese Mcdonalds. I spoke to the manager and here are the details.
You fire up your machine and open your web browser.
You will be taken directly to the website of
http://www.ptwifi.pt
On the top of the resultant page is a box for user login and password. Use the following user name and password:
username: mcdonalds@ptwifi.pt
password: mcdonalds
Hopefully this will work in all Mcdonalds throughout the Algarve and most of Portugal."
Certainly worth a cup of coffee.