Long-Tails are a DIY, semi-Mad Maxian, sort of boat common all across South East Asia. The typical blueprint for a Longtail is a normal canoe with a secondhand automotive engine attached to it. You see them all over Thailand and Myanmar and, if you ever go there, would probably end up paying a couple bucks to someone with a Long Tail at some point just to get where you're going. They're like water taxis.
But they’re also like racehorses. Each Long-Tail is different, the only common thread between them is that each one is a fusion of a normal boat with an automotive engine DIY’d onto it. This is VERY fast but clearly works for them well.