If you’re on the south side of the great geek/jock firewall, there’s something you should know: The 2010 Winter Olympics began today in Vancouver. Also, a tragic sled crash during a training run killed Georgian luger Nodar Kumaritashivili.

A good way to keep up with the games without gluing yourself to a chair in front of a TV is to hit Yahoo’s mobile site, m.yahoo.com/olympics.

Yahoo’s sports site is one of the Web’s post popular, possibly the most so. Yahoo built the mobile site from the ground up, rather than trying to serve HTML designed for laptop screens to your phone.

The company prepared a demo clip of the mobile site in action.

Yahoo’s mobile site doesn’t have video. But it does have still photos, plus live results and schedules of upcoming events. The site is filled out with blogs and expert commentary. You can search by athlete or by sport — luge, hockey, etc — for curated info. “If you’re a fan of Lindsay Vonn,” a Yahoo spokesman emailed me, “you can do a quick search and we’ll show you her athlete profile, which includes how many medals she’s won, her most recent headlines, her latest results, and even her birthday. (It’s October 18, 1984, by the way.)”

As proof that mobile sites are taken seriously, Visa and Samsung have signed up as sponsors. Advertisers are following the big spenders from television to the Internet and now to smartphones.