I spent some time working in the City of London recruiting people for quantitative finance for investment banks and hedge funds. One of the things I had to learn quickly was how all the different parts of the massive corporate banks connect. Shown on this map (which is interactive at the link) are companies that make up the Goldman Sachs group, which comprises thousands of business entities based all over the world.
You recognise the shape of the United States and the UK, but you may have to check the drop-down menu to identify the others. The area highlighted in yellow here is the Cayman Islands, where the corporation has 739 subsidiaries. That big red blob in Europe? That’s Luxembourg. You can move the mouse around to see each company and the other companies that it owns or is owned by.
It can get confusing fast. There are also visualisations for Bank of America, Citigroup, Morgan Stanley and JP Morgan, at OpenCorporates. Click here for all the different maps