In the ERE daily newsletter, David Lee asks "Are you Really Serious About Improving Morale?" . David posits that "goodies, gimmicks, and gala events" don't work (gotta agree with him there...these things can be fun but don't have a long-lasting impact on morale) but many companies take this approach to building employee morale. According to David, what works is "designing a work experience based on the plethora of research about which organizational factors, managerial practices, and human needs lead to an inspired, engaged workforce."
If you manage people or have any responsibility for employee morale, read this article.