I still celebrate Halloween with my Wiccan family as Samhain. Although I do not literally believe that spirits walk around that night, giving us the opportunity to commune with them, or believe a variety of other Wiccan things not directly connected to Samhain, I still find it to be a valuable ritual of rememberance of those who have passed (we bring a picture and a small paper of our memories and share them before burning them in an act of release, we pass a chalice of grape juice and a loaf of bread around in a show of community and mutual support for one another, we offer the Challenge to one another to show that in the Circle, as in all things in life, we should confront our fears rather than letting them rule us. Yes, I find there to be many good things about Wicca despite the fact that I'm *technically* an atheist.)
I'm also leading a Samhain celebration at my church, in which we are going to dress up in costumes (just for fun). And I'll probably go to a couple parties with friends or something like that (maybe rent scary movies afterwards, I dunno).
I wish I were still young enough to go trick or treating!