Sinister Groups or Glorified Think Tanks?

Recently I was asked if I had come across the Club of Rome, which I hadn't, but I have found their website.

There has also been interest on the internet and elsewhere, to the point of obsession in some quarters, with a group called Common Purpose.

Now I am naturally quite a sceptical person and don't see conspiracies around every corner, but I am intrigued when people do see conspiracies in what may be innocent groups or events. I have had a brief look at these websites and, while being dubious about them from a political and moral perspective, have yet to discover anything truly sinister or conspiratorial. Others may disagree.