I was playing Arena the other day and one of my favourite features is the calendar system. It's so simple but IMO adds to the immersion ten fold. It's interesting to see what "holidays" Tamriel celebrate and what offers the stores have on.
It got me thinking how this could be implemented and expanded in a modern day Elder Scrolls days. I'd love to walk through Windhelm during the Feast of the Dead, seeing banners around the place and the denizens singing songs and drinking mead, walking upto a blacksmith and seeing he has a 50% sale on all his items. IMO it would add so much more depth to the world.
So what do you guys think? A nice idea? Or an unnecessary feature?