My LS is not driven on wet snowy/salted roads. All I do in winter is to take it out on a crisp, cold day when there is no splashing and drive it for 40-45 minutes. Occasionally, I will drive it to work. Sometimes 1.5 to 2 weeks will go by in between drives, and I have had zero battery issues.

This includes the current winter, which is noteworthy in that my battery is almost three years old AND it was fully discharged once last year. It is, however, holding up like a champ through this winter (of course, because I said this, the car won't start next time ).

A battery tender wouldn't hurt, and I almost got one last winter, but in the end a nice, long drive every now and then should do the trick.