Stay in touch with your clients during the holiday season. You can still send Thanksgiving cards and tell your clients how thankful you are for their business.
Do you think it will take too much time? Too much work to handwrite all of those cards? Then check out http://www.sendoutcards.com/. You can upload your contact database in one stroke and send out cards in another. You can even do it in your own handwriting! What are you waiting for? I'm sending mine out now!