What’s The Santa Claus?

With Christmas and the birth of my first child drawing near, I got to thinking about good ol' Saint Nick. Over the next few (or more) Christmas season's, how will I address the big red elephant in the room? I want my kid to believe in the magic of Santa, I want to give him/her that special childhood experience. It's only a small window, after all, but to what length do you go? How elaborate should this lie be? It kind of seems a little wrong if your child keeps asking you different questions and you stack up more lies to give him/her this fairy tale.

This really isn't a big deal. I'm sure I will just tell them the truth as soon as it does feel wrong, but I was curious as to how parents out there have dealt with this? Do you tell the truth, tell a few little white lies, or change the subject? Those of you that celebrate Christmas, please merrily chime in.