If you still haven't explored the marvelous adventures in The Elder Scrolls Online, now is a pretty good time to do so. If you have Xbox One and Xbox Live Gold, all you have to do is collect a couple of good friends and start playing on Thursday.
The Elder Scrolls Online is completely free to play until Sunday, and there's also a discount during the very same period of time if you want to continue playing (60% off). There is also a free promotion on PC, but in order to enjoy that you'll need to get a code from somewhere (sorry, we don't have codes).
Bethesda also confirmed that they are working with Sony to find a solution to offer something similar on PlayStation 4 in the near future.
You can find full details on the promotion over on the official website.