NEW YORK (BLOOMBERG) - Think bitcoin's surge of more than 30 per cent in the last week is impressive? Check out what some of its cousins are up to.

The market capitalization of digital currencies has soared over 50 per cent to more than US$90 billion (S$124.6 billion) in just the past seven days as the frenzy around cryptocurrencies reaches a fever pitch. Demand is swelling as more companies embrace the technology backing the method of exchange and some investors see it as a haven from political uncertainty across the globe.

Numerous alternative cryptocurrencies, or "altcoins," have emerged since bitcoin broke into public consciousness in 2013. Companies can sell new tokens through initial coin offerings, or ICOs. Ether, a digital currency linked to the Ethereum blockchain, has more than doubled its worth in the last week and is currently the second most valuable cryptocurrency, behind bitcoin. The value of zcash, the cryptocurrency that announced a partnership with JPMorgan Chase & Co on Monday, has grown by nearly 200 per cent.

Bitcoin's slice of the pie has shrunk recently as its peers have gained share. It now dominates about 45 per cent of the overall digital currency market, down from around 85 per cent in February, according to data from CoinMarketCap.com. Meanwhile, Ethereum's share has increased to more than 20 per cent from 7 per cent in February.

As for bitcoin, it smashed the US$2,000 mark on May 20 after soaring nearly 65 per cent in the last month. CNBC pointed out on Monday that if you bought US$100 in bitcoin seven years ago at the 0.003 cent price on May 22, 2010, it would now be worth almost US$73 million.