[neboysa]

Actually, very often they don't... Porsche shares, if you wish, are the representation of the public perception of value of their cars, service network, brand, cash in the bank, etc. They are the quantifiable proxy of those values. Cryptocurrencies do not proxy anything. So, the only way to measure their value is by "what people are willing to pay". And that doesn't have to be bad, a-priroi. Its just different thing. So, the cap of crypto _is_ nr of coins time price per coin, where ppc changes heavilly over time. So the "market cap" of crypto is not constant - it changes very rapidly over time. <crypto_name_here> could have a cap in billions today and zero next Thursday. Hence, there isn't much sense in trying to define/measure it.