I've got one!
I keep him in a 4ft (145l) tank with plenty of hiding places and plants. I have a shoal of juvenile Bosemani Rainbows, some Plecs and a Half Banded Eel in with him. The two eels despite being different do hang out together happily.
I have found he (both eels really) only eat live or frozen food, blood worm is favourite. They will not entertain pellets of flake (they have taken the odd mouthful and spat it out in disgust)
One word of warning though, I did have 2 Zebra Spiney Eels, the other one committed suicide by escaping from the tank so make sure all holes are covered and keep a close eye when you lift the lid!
Other than that, the eels are a lovely, unusual addition to the tank, very visible and both of my two will eat from hand now. The Half Band comes to say hello whenever my other half puts his hand in front of the tank! Lovely fish.
(mine are only small, about 12cm so no problems withthem eating other fish but I am sure they would eat small fish if they could! they have eaten krib fry...)