Not sure what "free Gold membership for the weekend" means other than "free multiplayer" - and maybe taking advantage of the deal of the week. But all European gamers get it May 1-4.

The annual event promises to offer gallons (sigh ... Imperial gallons) of fun with all of your favourite Xbox multiplayer titles. In addition, a rush party staff spanning 10 countries and languages will be on hand to proselytize on behalf of Microsoft.

Xtival is Back [Microsoft via The Gamers Magazine]