The Wikipedia article for the South Sea Company says that: "Among the many companies to go public in 1720 is - famously - one that advertised itself as 'a company for carrying out an undertaking of great advantage, but nobody to know what it is'".
I was curious as to whether anything ever came of this company, but a google search yielded no real further information on the company. Was this just another company in that investment-frenzy phase, or did it ever amount to anything more (and what did the company actually do)?