For a quick burst of activity, then I’m happy to buy a coffee (or tea at any rate), and use free WiFi for a short while.

If I’m using the internet regualarly on the go, then I’d go with a broadband package of the type mentioned. Of course I might not be streaming too many videos from YouTube via 3G, or buying any movies from iTunes (not that I would anyway).

Personally I have a PAYG O2 dongle. No ongoing monthly bill: £2 for 24 hrs, £7.50 for 7 days or £15 for a month when I need it. Plus unlimited WiFi via The Cloud/BT Openzone (a la iPhone contracts) for those fast WiFi speeds.

As for sockets in McDonalds: just look for the safety blankers they put over sockets to keep small children’s fingers out. They are removable!

One thing to check in your search for a new laptop: long battery life. That way power supplies won’t be such an issue.

I’ve a meeting at 4pm in W12, and have just had a meeting here in Earl’s Court, so you find me replying to this email, fittingly, from a place that sells coffee – using my broadband dongle. As a commenter on my Flickr photograph has said, £10 for broadband for a month seems rather a better deal than, say, £2.40 for a fluffy coffee to get 30 minutes’ worth of broadband…

Check out this WSJ piece, linked to from a similarly themed piece by John Naughton.

Your list of outlets, incidentally, excludes perhaps the most prevalent purveyor of free WiFi – McDonalds.