This winter is tough. The measures I'm taking are:
1) I have a full-home humidifier now, actually picked it up last winter. I have to fill it once or twice a day (when it's really cold/dry), but it keeps the whole house near 65%, and it cost less than $100. This obviously helps cigars, but it helps our health even more--I typically get nose bleeds all winter, but have not had any this year.
2) The room I leave my cigars in is usually like 50-55 degrees in the winter, but now I leave that door open to let the heat from the house in, and it's over 60 in there now. I know that some people don't think cold alone effects cigars, but last winter I had dozens of cracked cigars by spring, and can't attribute it to anything else.
I have 12 Red Tubos right now, 2 arrived with very minor cracks, but nothing obscene. They have not gotten worse, and I'm storing them w/o caps to get them to my preferred 65%.