Colour me skeptical (thats a shade of red I believe) - the problem is that all of this comes down to peoples perceptions and the way that they remember them, the other explanations are overlooked; for instance waynetravis mentioning the pipe anecdote, now smell is a sense that is works around the way that our olfactory receptors bind to odor molecules, now given that the man smoked in the house and may have lived there for a prolonged period it is entirely likely that smoke and tobacco are still in the house; especially if it has the same carpeting or layer beneath, there is the possibility that a current occupant smokes. The alternative is paranormal - that somehow the receptors are being stimulated by a supernatural entity or that is summoning tobacco smoke molecules into existence. We all see things, reflections and odd tricks are the usual cause, even strange noises (for instance I heard a strange humming in the night, sporadic and very eerie - sounded like a theramin - and I didn't know what it was, then it knocked my books off their shelf, shock and horror the pipes had stopped working in the house and the shuddering was a case of water hammer and not the paranormal).
We all have the ability to percieve events and if we want to believe then we can fill the gaps in - even if they wind up frigtening us. Just take a kid or believer on those "ghost tours" and they can be scared out of their skin - hell me as a 10 year old with a hyperactive imagination was able to do it very effectively. Even today when I say up for extended periods (36 hours +) I start hearing voices - my mind fills in gaps within random noise, I hear my name being called out; although to be fair these all occur in places with a large number of people).
An example, Port Arthur ghost tour in 1996 (I am pretty sure in January before the massacre), I go on this thing when I am 10 and am thoroughly engrossed by it and the ghost stories - we get to a part of the tour and keep in mind it has been building, we visited the morgue and the church, all eerie places - anyhow last part of the tour is like a mill or something, the tour guide begins talking and I feel a really strong tingle on my right leg, and as I listen it ultimately turns out that a guy burnt to death in that very mill - now taking all this at face value and given that it began tingling before the guide mentioned the whole burning part it could validate my views about ghosts. But in doing I would be suspending logic, we all get chills and tingles - on a cold night after walking around especially so.
If you genuinely have and can verifiably prove the existence of ghosts then please claim the Randi foundation prize, proving the existence of ghosts would not only make you rich but would overturn our very understanding of biology and how matter exists in the universe.
I suppose that the supernatural just never want to come out and play for the skeptics
http://randi.org/