I read about this stuff in Andrew Loog Oldham's biography. It's some sort of Absinthe like thing made from potatoes and apparently has existed in Ireland for hundreds of years. I have never heard of it, but I wonder if this is the sort of thing you can buy in Ireland (like is it actually legal)? Sounds like strong stuff.
It's essentially a very strong neutral spirit made from potatoes, potato vodka. It is now legally made in Ireland. The reason that it has been the source of trouble in the past is;
1. its strength
2. the mash was distilled through copper tubing that was often recycled from industrial use and picked up residual chemicals.
It's rotgut stuff and the only effect it has on people that could be considered akin to absinthe is that it gets you very drunk.
From what I have read, it is still made in Ireland, mostly in the West of the country. However, it often uses starch that has been discarded from other processes. I think that in order to find some that was safe and worth drinking you would need to speak with some locals in western Ireland. Also, each moonshiner probably makes poteen differently.
I've been a moonshiner for many the year,
I've spent all me money on whiskey and beer.
I'll go to some hollow and set up me still, and
I'll make you a gallon for a ten shlling bill.
That's the start of an Irish traditional song.
Well, it was a pretty funny description in Mr. Oldham's book. It sounded like Sean Connery and Princess Margaret were both speechless and glued to their chairs (and his wife at the time spent two hours hiding in the bathroom). I wouldn't think plain old moonshine would produce that "extreme" of an effect if you know what I mean. This is why I was curious.