I gained an appreciation for sumo when I lived in Japan, but I've never been able to keep up with that sport since I moved back to the US. It's a strange sport: fast, ritualistic, confrontational, and absurdly athletic. The prepatory purification rituals are as much a part of the aesthetic appeal of the bout itself, and some of the kimarite (決まり手) can be amazing.
I attended a basho in Tokyo about 10 years ago, but for the most part, the way to watch it is the daily recap on NHK. Hopefully, once the next basho starts, I'll be able to figure out a way to watch these online. Every time I've thought to check when the next basho will be, though it turns out that I just missed it, and have to wait another two months. As it turns out this time, the Nihon Sumo Kyokai says the Kyushu begins this weekend. & soon the Japan Times sumo section should have some info.
Winter certainly seems like the time for some chanko-nabe.