Of all the foods that I'm aware of, there is nothing that quite provokes the response of "ewwwwwwww" as much as Haggis. Not because people have tried it, just because they've heard what it consists of -
There are many recipes, most of which have in common the following ingredients: sheep's 'pluck' (heart, liver and lungs), minced with onion, oatmeal, suet, spices, and salt, mixed with stock, and traditionally boiled in the animal's stomach for approximately three hours.
Hmm, having just read this, I've realised that I may not have had the full haggis experience - though it's a little vague as to whether you are served the stomach as part of the meal or it's just used for cooking. It's also traditionally served with mashed potatos and turnips (or "neeps and taties")
Now I realise that this isn't the best picture - I'm much better with Photoshop than Gimp when it comes to fixing colours - but hopefully it gives the gist.
Haggis to me tastes a bit like a nicely warmed pate - that rich, warm and full flavour with a little extra spiciness to give it a little kick. The texture is like lumpy mashed potatoes, with some of the lumps (which you can't see as much as sense) being something that you know is bits of offal but not disturbingly so. It was served with a range of sauces - French mustard, Brown sauce and something else - but these weren't needed as the mashed potatos and turnips worked fine with it and I really can't see why you'd need any extra flavour.
I liked it and I'd eat it again - good hearty comfort food.
The people I've mentioned eating it to so far have still had that awful/offal reaction, but really, if you think about the things that we have no problem eating (like sausages) - what's the difference? If you're going to eat one part why not eat another. (Though I will draw the line at tripe on the grounds that it tastes horrendous)