They’re really, really good to eat. Very rich, with excellent flavor. The small ones are best, otherwise, as my best friend remarked, it’s like eating a penis. (A big part of the reason he’s my best friend is because he allows himself to be pressured into participating in disgusting pasttimes like this.) If you do find yourself with one of approximate penile thickness, avoid cutting it into approximate penile length, it’s pretty disturbing.
They’re hard to handle and difficult to kill, so you’re going to have to resign yourself to lots of mess and blood and guilt and tears. Think of it like a lobster, too stupid to feel pain. True? I have no idea, but it makes me feel better.
Grab the eel with a rag, which is easier said than done because the moment you grab it, it twists around the rag, your arm, and the nearest drawer handle with surprising strength. It will be trying to bite you while secreting more eel goo, which is another reason to go for the smaller ones. The big ones bite harder.
Now, kill the eel. I won't go in to exactly how, because opinions vary, and nothing really seems to work properly.
Now, once you're sure the eel is dead, using another knife, cut through the skin below the head, all the way around. Now take needle nose pliers, and gripping tightly (I can’t stress this part enough), peel off the eels skin like a sock. Now, turn it over, gut it, clean the body cavity, and cook. I find a perverse sort of fun in the eel fishing itself, and even the cleaning and messy stuff is all worth it the end, as it’s pretty much the only way to enjoy a geniune Unagi bowl in Switzerland. They're also damn good grilled on skewers with bacon and sage.