The other day, one of the opera devs wrote an article detailing extended Javascript functionality for the Wii Opera Browser.
http://dev.opera.com/articles/view/the-wii-remote-api/
With this you can capture all the details about the Wii-mote, when someone views your page. You can capture the tilt, the position, and the button presses of all 4 wii-motes currently in use.
I started playing with it a little bit, but didn't really put forth a lot of time getting anything right.
http://www.theschlock.com/games/wii.html
I ended up just copying one of the examples..
Note: This wii-mote API is only available for Wii Opera 9.1, which is the current version of the software. Those old trial and beta versions are 9.0, and do not include this.