The Christmas holidays are the perfect time to celebrate. And a celebration can, and should be, centered on meaningful expressions, that are not necessarily tied to religious beliefs (i.e. the end of a good fiscal year, surviving a tough economy or an appreciation for what you have).

I prefer giving gifts that the client can actually use or will remember well past the holidays. Free shipping, account upgrade, a gym membership, a service, magazine or recreational subscription; or a monthly pizza delivery for the office, will have a significant impact on your business being remembered. Or surprise a client by organizing a crowd sourcing collaboration focused on their core business. Also, picking up the tab for drinks and dinner can be much more cost effective (and more personal) than purchasing advertising in a trade magazine.
My mantra is, 'Give the unexpected that is so unique and innovative that it causes customers to remember, and competitors to envy, the way you do business'.