Mt. Rainier is my favorite place in the winter. If there is fresh snow, rent a pair of snowshoes and head up to Paradise. At the parking lot, go East, up into an open area with a few stands of alpine fir. If there is snow on trees, it's a great photographic experience.
Note: The road up to Paradise usually does not open unitl 9 AM, so plan accordingly.
I have a few images of this area on my web:
Go to the landscape page and scoll nearly to the end. They are BW shotsImageNorthwest