This idea is so easy. Most of us spend too much time online so why not put some of your online time to a great purpose by sharing the gospel with your friends (this of course will make their online time more meaningful as well).
You could do a Christmas version of one of these ideas: the share an evangelistic website, leave an evangelistic Christmas status update, share with someone new right now or share a customized survey with your facebook friends (these came from our list of evangelism ideas).
You could also send out an e-mail with a nice Christmas note and the Christmas message or you could send a Christmas e-card like this one (find more Christian e-cards here).
I never forward forwards but every once in a while this time of year I will get a really good Christmas forward. You could forward something like that to your friends. See an example I received today below the video at the bottom of this post (thanks Wendell!).
Link a video like the one below on any of your online witnessing applications (here's the link) and check out even more ideas here; whatever you do, bring Christ into your internet world this Christmas! Get more Christmas Evangelism ideas here and have a wonderful Christmas!
Here's an example of a forward I got mere moments after posting this post: