We headed up to Great Falls on January 22nd. It was 21 degrees, and freezing from the start. After one run of Maryland lines and a swim, we decided that we were done for the day. And chilled to the bone.
Then we found ice, and lots of it. Two hours of fun ensued.
There's a small bit about this on my blog: http://fluidglass.com/2011/02/bringing-this-blog-back-to-life/
Also, let me know if you like the headcam audio with the music or if it's too much.