Microsoft has announced that the Xbox Live Gold service will have be free to all from October 4th until October 6th. This will unlock access to everything to behind the Gold paywall including online multiplayer and various media apps including Netflix and LoveFilm, though you obviously need separate subscriptions with those services to use them.
There doesn’t seem to be mention of the Games For Gold promotion but I assume that will also be unlocked during the free weekend, which will allow you to download Might & Magic Clash Of Heroes to keep forever. I might go back purely just to download that, and maybe take part in a bit of multiplayer.
Going by the official list it looks like most of Eastern Europe won’t gain access, with the likes of Russia, Ukraine and Poland missing out.