Howling Mine is, and will always be, a classic! It's been around since the beginning of Magic (Alpha) and has been reprinted numerous times, though most of them being in Wizards of the Coast's Core Set series. I played with this card just to play with it. I didn't care if it made sense in the deck or not. It kind of defeated the purpose of my Ensnaring Bridge usage!
What I liked as a side-effect from using this card, was that a lot of times players left you alone, because the card also benefited them. Not so much if you were playing Mill, though, as this would quicken the path to their demise!
Above are my two foil 7th Edition Howling Mines. Regulars used to be upwards of $15-$20, but now you'd be lucky to get a few bucks. These foils, however, may be worth a decent penny. I just noticed that this one has a little foil bubble mark on the mid-left side of the card. At least I believe that's what it is. Too bad it doesn't take up half the card! I'd have a really sweet misprinted card then!
Cripes, I've forgotten to check what misprints I have. I love misprints! Almost as much as foils...
No guarantees, but I'll take a gander.
As for Howling Mine, it will always have a place in my heart, and likely my decks! If I were to build any...
Have you ever played with Howling Mine? If so, what kind of decks to you use it in? Do you have any misprinted cards?