The six-figure campaign, created by the start-up Albion, breaks at the weekend on posters in Tube stations.
The ads feature bold copy in Virgin's trademark white on red, describing situations that seem like a good idea at the time but which people later come to regret.
One mentions "getting the milk in the buff" and "volunteering to drive the in-laws to the airport". Copy at the bottom of the ad reads: "Virgin.net broadband. No 12-month contract. Free anti-spam e-mail and virus protection. www.virgin.net." The ads are supported by direct mail, e-mail and an online viral game.
Peter Tuomey, Virgin.net's sales and marketing director, said: "Virgin.net and restrictive contracts just don't fit together. Our brand is all about fairness, openness and honesty so, unlike the vast majority of ISPs, we don't force our broadband customers to sign a 12-month contract."
The work breaks this weekend and will run until November. It was written by Matt Gibbins and Tim McNaughton and art directed by Darren Hughes.
Media was through Manning Gottlieb OMD.