After 160 years, the melancholy genius Edgar Allan Poe finally has been given a proper funeral. The CBC site has a pretty good rundown of why Poe was given short shrift during his first sendoff back in 1849, along with details of what the good people of Baltimore did yesterday to make up for it.
For me, The Cask of Amontillado was the first Poe story that I read as a kid, and still has the power to make me squirm a bit with the thought of the helpless terror of a person being walled-up. Because it's one of my favourites, I always get a bit of a smile when I rewatch the episode of Babylon 5 where Bester the psicop quotes it. The Raven, of course, is another one that ranks fairly high up, and I loved the Simpsons' rendition of it in their first Hallowe'en special - still have that one on tape after all these years. Other favourites of mine include The System of Dr. Tarr and Prof. Fether and Some Words with a Mummy.
But as Poe is regarded as a master of horror, I have to say that of his works, the story that I've always found most frightening is The Facts in the Case of M. Valdemar. I won't give any spoilers for this one, just the recommendation. If you haven't read it yet, find it and experience it for yourself.