@larand I honestly had to look that up, and yeah, wow! Found some lovely descriptions over on wikipedia:
The late chef Anthony Bourdain described kæstur hákarl as "the single worst, most disgusting and terrible tasting thing" he has ever eaten.
and
Chef Ainsley Harriott, during his series Ainsley Eats the Streets, was unable to handle the heavy ammonia taste and described it as "like chewing a urine-infested mattress".
Absolutely amazing! ?