I am a huge horror fan as well and the only thing that comes close for me is Pennywise in Stephen King's It.

To this day, no one or no thing is scarier than Bob, or at least I haven't come across it.  Any characters or monsters out there as scary as Bob? 

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

Monsters? Well, what about John Carpenter's Thing, or Ridley Scott's ALIEN? In front of them, BOB is just a man who need to shave and to wash and cut his hair....I think that atmospheres in Bob's scenes are really scary, maybe much more than Frank Silva himself as an actor...I always thought that Leland was the true scariest character in the series....Because of a superlative interpretation of our dear Ray Wise. Ray Wise's face is THE scary mask itself.

Sonia

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

So Bob looks human and the knowledge that he is not human is created by the evil atmosphere that surrounds the scenes in which he acts...That's why he's so scary and that's what I was trying to say before. If we met Bob in the street, in everyday life, could we be so scared? Frank Silva's face is not more terrifying than the Alien's fangs...I even prefer the Little Man's doppelganger! Black Lodge doppelgangers, Laura who screams whit yellow teeth, Alien, The thing, Freddy Krueger, are scary for the simple fact to be scary themselves.

Bob is another category of scary characters, the ones that take form from evil atmosphere that surround them, such as Jack Nicholson in SHINING...So, in this category of scary characters, I prefer SHINING...

Sonia

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

When I was 17, at night, in a cul-de-sac, I made a thief with a knife run....And thief's face was not what we could call the rapresentation of Beauty. Am I scarier than Bob?

It may be...

The answer is: atmosphere. At night, all cats are grey. In the light of the day, some cats are ugly, some other are not. Frank Silva is not.

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

Stanley Kubrick is a master of creating a spooky atmosphere with his visual directing style (i.e.the long hallways), but there wasn't a particular apparition in that movie that was as scary as Bob.

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

Even THIS? -----> http://upload.wikimedia.org/wikipedia/it/e/ef/The_Shining.jpg

The character of Jack Torrence is the prototype of BOB. He's the historical resident evil!

NO WAY!  That scene is like a joke now because it has been parodied so many times - "Here's Johnny!"

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

A greasy, long- haired, scuzzy supernatural demon vs. an alcoholic human driven mad by a hotel's ghosts?

TKO.  Bob wins in a knockout.

 Next villian please. :)

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

There is no way an actor that was on Wings could be scarier than Bob.

I never saw the remake, I heard Stephen King made a cameo as part of the band and the name was a reference to Pet Sematary.

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

It's funny how we all have different perspectives and reactions to things. I guess that's what keeps TP so fresh and relevant and interesting and makes me want to revisit it so much. 

Bob is almost a beast in human form.  Jack Torrance is Jack Nicholson acting like he's crazy(which probably isn't too much of  a stretch). :)

 What made the Blair Witch scary to me was that you actually never saw the Blair Witch.

Which gives Lynch and co. even more kudos because we see the demon Bob and he is something out of the worst nightmare imaginable!

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

The true work of ART is the interpretation of Leland, in which Ray Wise let us sometimes see, sometimes guess, all the pain, the torture, the madness and the evil of a possession. Ray Wise is a great actor. Bob, the Bob you are scared from, maybe lives in HIM and in his character much better than in Frank Silva. I think you could agree...So come on, have a cup of black coffee, friend?

Sonia

Ray Wise was definitely creepy and his acting was of the highest level.

Lynch and Co. created Bob, and it is a combination of Frank's physical appearance and Lynch's knack for being able to make the most mundane unsettling.  But, yes, I still think Bob is the scariest creation in TV and film, and that says a lot for character on a primetime "soap opera." 

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

Bob does need a bath and a new wardrobe.

 Visually, I thought there were some scary characters in that early 90s remake of Dracula with Gary Oldman (him licking the bloody razor, etc.)

Bob is the undisputed heavyweight knockout villian  of all time and I mean that as the highest compliment :) 

"Harry, I'm going to let you in on a little secret. Every day, once a day, give yourself a present. Don't plan it, don't wait for it, just let it happen. Could be a new shirt at the men's store, a catnap in your office chair, or two cups of good, hot, black coffee. Like this."  -Dale Cooper

SPOILERS for the film DON'T LOOK NOW!!

The dwarvish thing/old lady/whatever at the end of DON'T LOOK NOW with Donald Sutherland (who is viciously stabbed by it) is IMO scarier than BOB.... A dwarf with red clothes who is a bigger motherf*cker than the LMFAP...