Here's a new twist on subscription marketing: Mad.co.uk, who publish trade magazines for marketers in the UK, just sent a broadcast email to their opt-in list offering "£100 FREE British Airways Holiday vouchers with every mad.co.uk subscription!" Unfortunately the email's subject line was the stunningly-bland "Special Offer" but who knows - that might work in the UK.
I used to be the US copywriter for a very famous British publishing company and was always stunned at how utterly different a copy that got Brits to respond was from American copy. Veteran Al Goodloe of Publisher's Multinational Direct once told me great American copy, when translated properly, would do very well in almost any country on earth, including Germany, France, Pac Rim, etc. Any country, that is, except Great Britain where you simply have to hire a native. Our "language barrier" is too deep.
Link to Mad.co.uk's offer:
Link to Publisher's Multinational Direct