Prices start at £2 for one days' Wi-Fi access as you travel around London.
A weekly pass will cost £5, and a monthly pass comes in at £15.
Any O2 and 3 customers who live or work in London will smart at these prices – and that's Virgin Media's basic intention.
It's not offering underground Wi-Fi out of the goodness of its heart, after all; this is a hardcore business decision, with free access intended to sweet the company's TV, broadband and mobile deals.
Similarly, customers of EE (including Orange and T-Mobile) and Vodafone will continue to get free Wi-Fi on tube platforms when the universal free service ends in early 2013, thanks to new partnerships struck with Virgin Media and announced today.