The original Omen from 1976 was released on the less satan-stirring June 25. They got a couple of sixes in their release date (June, 1976). I personally like the fact that in Australia way back in 1976, the film was released two days for Christmas Day! But 06/06/06? That's gold.
If you can't go to the cinema today (or, lets face it, you really don't want to see the remake in the slightest) you could watch some devilish movies. In the mood for comedy? How about Bedazzled or The Witches of Eastwick (starring the HOLY TRINITY of actresses Michelle Pfeiffer, Cher and Susan Sarandon + Jack Nicholson as the devil) or, hell, even Woody Allen's Deconstructing Harry. That one has Woody's character taking his son and a hooker to a college ceremony. All very Wild Strawberries. Harry is a bit cockeyed for my liking, but Billy Crystal makes a good devil incarnate. The Devil and Max Devlin is unseen by me, but... i dunno. You could check it out? There's also the sequel to Oh, God! (a mildly interesting comedy) in the form of Oh, God! You Devil! (what looks to be dreadfuly). Lastly, there's the South Park movie. I'm pretty certain it's the only film in existance where you can see Satan and Suddam Hussein be homosexual lovers (just a hunch of mine)
If you're in the mood for action there's Arnold Schwarzenegger doing battle with CGI demons in End of Days or Keanu Reeves doing battle with CGI demons in Constantine. They may very well be the exact same movie, but Constantine also has the added bonus of Tilda Swinton and Rachel Weisz so if that's ur bag go with Constantine!
However, if you're looking for horror goodness then this is where Satan outdoes himself. Apart from the original Omen there's Mia Farrow discovering her pregnancy is all part of some wicked cultish devil thing. I personally haven't seen this one (I want to desperately) but I do know it has one of the creepiest posters OF.All.TIME. (you can see it below, folks).
On the lame side of proceedings are two god-awful movies that I regret even mentioning but I feel like I must. The atrocious Denzel Washington-John Goodman (yeah, I KNOW!) Fallen is out there for all of the world to see (and realise it sucks). It's all about how the devil can pass through you by touch or some bullshit like that. i hated that movie and wish it would die a thousand Satanic deaths. There's also Patricia Arquette going all bloody-palmed on us in the really quite ridiculous Stigmata. In that one you can see Patricia go all, well, stigmatic (is that the word?) while one of the dullest actors ever stands around in a Priest outfit (I speak of Gabriel Byrne). Or, better yet, you could not and live happily ever after!
Now of course, I leave the best til last. The Exorcist. One of the rare moments when the Academy actually clued in and nominated a horror film. This one, as we all know, as the head-spinning-pea-soup-vomiting Linda Blair as a little girl possessed by the devil. Ellen Burstyn stars as her mother and Max von Sydow and Jason Miller star as the two priests who come to banish the wicked one. Do not go to the video store and accidentally pick up the prequel Exorcist: The Beginning (the poor grammar of the title should tip you off) because that one is vile crap - although apparently Paul Schrader's original prequel (y'all remember how Paul was dumped and they made a completely new version) is quite good. Anyway, the original 1973 version is the best, and features one of the scariest frames of film ever. You can see what I speak of here. The first time I saw that face in the kitched was frightening to say the least.
Other random titles you could also watch are The Devil's Advocate (with Keanu Reeves, Al Pacino and Charlize Theron), The Ninth Gate (Roman Polanski directing Johnny Depp).
Oh, if you're not in the mood to watch a movie, read The Devil Wear's Prada! I know it's not about the actual devil, but whatever. You can prep for the movie that's out in 5 weeks, starring Meryl Streep as the titular Prada-wearing Devil and Ann Hathway (fresh from her Brokeback Mountain breakthrough).
Anyway, enjoy this most devlish of days. Don't get drawn over to the dark side or anything cause... ya know, that's be bad (by "dark side" I obviously mean Scientology)