The church my friend Liz attends put on a Celtic Fair, though mostly it had a Scottish emphasis. She invited me to come and have a lamb dinner with her. They also had a haggis and I tried some. It wasn't too bad, though I was nervous that it would be gross.
For the non-haggis eaters among you, this is kind of like a hash/sausage combo. They take the parts of the sheep (or cow in this case) that are less desirable (like heart, liver, etc.) and cut it all up, mix it together with some onion & spices, use oatmeal as a thickener, put it all in a casing and boil it. Traditionally the casing is a sheep's stomach. Thankfully, this one was not...the casing looked more like red plastic wrap. The taste and texture reminded me of flavored ground beef. I kind of mixed it with the potatoes to get it to hold together.
So I wouldn't want to eat this every day, but I'm glad I can say I tried it. And no, it did not taste like chicken.