It is actually quite common in Canada for small companies to IPO with total market caps of just tens of millions of dollars. Canada doesn't have nearly as many private company investors as the USA, so companies (especially resource based companies) just go public when they are small in order to raise money.

All these small company IPOs are on a separate exchange (the TSX Venture exchange), and if the company gets big enough, they 'graduate' to the main exchange. This works because the regulatory overhead of being public is a lot less in Canada on the TSX Venture exchange - No Sarbanes Oxley!

London has something similar with the AIM.

I think it is a better system than the US model, because it allows anyone to invest in the small companies, not just venture capitalists or people who participate in specialist schemes to buy private company shares.