Sky is taking a leaf out of Microsoft's book with the news that the broadcaster is encouraging those with Sky+HD to hold movie-watching parties in order to persuade their guests to sign up for the high def service.

Each party host will get one free film - either "Harry Potter and the Half-Blood Prince", "The Hangover" or "Angels and Demons" - from Sky Box Office HD, worth £3.91 and a £10 M&S voucher to buy some vol-au-vents or the like for party snackage.

To qualify for the offer, party hosts need to set up their Sky+HD party online and invite three or more friends (over 18 and not members of the household) who must accept their online invitations by 5pm on 17 November.