Curling is seriously under-appreciated. .
John was constantly learning new things about Sherlock. Some things were fairly straightforward – odd habits, things that would irritate him, what he enjoyed eating, etc.
Other things, however, were completely out of left field. Sherlock's fascination with curling was definitely one of the odder things John had learned recently. He never imagined Sherlock to be the sporting type, and to an extent, he wasn't. Half the time he wasn't even aware of what countries were competing in a particular event, no idea what the players' names were, where the game was currently being held. That was all extraneous information, irrelevant to his enjoyment of the game.
For Sherlock, it was all about the physics. The friction of the surface combined with the angle and force and sheer grace of the stone sliding across the ice. "It's like billiards, John, only on a much grander scale. What's not to find fascinating?"
When their first Christmas together rolled around, John racked his brain for a gift. Nothing he looked at seemed appropriate, until Sherlock marched imperiously into the sitting room and informed him that the day after Christmas they had to head up to Scotland for a case.
Christmas morning, John handed Sherlock an envelope. He watched the grin spread across his flatmate's face as he pulled out two tickets to a bonspiel.