Blockchain enthusiasts are cashing in on the cryptocurrency gold rush by making their own hardware rigs for mining tokens like zcash and ether on the Ethereum network. “Mining,” or computational accounting, is the fuel that runs the blockchain networks behind bitcoin and zcash. In theory, anyone can earn bitcoin or ether by contributing a little bit of computing power to the network. Now Craigslist, eBay and social media are swarming with DIY tutorials and techies peddling pricey Ethereum rigs for mining cryptocurrency.

People can use a regular old computer or laptop to mine Ethereum, as long as the machine has a graphics card (GPU) with 2 GB of RAM. CNBC reported the bitcoin boom is driving up demand for AMD graphics cards. Retailers like Best Buy and Amazon are reportedly sold out of most AMD RX 570 and RX 580 graphics card models, even at  Canadian outlets. So people are making their own makeshift hardware from Colorado to New York, cryptocurrency rigs that can cost upward of $5,000.

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Mining cryptocurrency takes a lot of processing power. So many people prefer to run external rigs so they can rake in alternative coins on the side without sacrificing their regular digital habits. One TweakTown blogger claimed he makes more than $850 a month mining cryptocurrency.

"We can't build the rigs fast enough," Scott McCarthy, CEO of the Los Angeles company SMS IT Group, which sells mining rigs, told Motherboard. "I get more calls then we can handle right now. We will take a deposit but tell the customers they have to wait up to three weeks before we can deliver. I got over 20 calls this past weekend from people looking to buy a rig or take training classes."

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Meanwhile, reddit users are helping each other build their own rigs for a fraction of the cost. However, these DIY machines require maintenance and upkeep. So buying or building an Ethereum rig doesn’t guarantee easy wealth. “I think it's safe to say that mining shouldn't be seen as a get-rich-quick scheme for people that aren't really concerned about Ethereum or cryptocurrencies in general,” one reddit user wrote.

This same trend is unfolding in South Africa, where the company Bitmart sells ready-made hardware for mining bitcoin, Ethereum, litecoin and dash. Several of these hardware products are in such high demand they are already out of stock.

The whole point of a decentralized blockchain network is the mining process was supposed to democratize cryptocurrency. Allowing everyone to contribute based on participation instead of purchasing power could theoretically prevent monopolies. Yet the Atlantic reported industrialized bitcoin mining operations in China already reveal the system is vulnerable to manipulation. It remains to be seen if the blockchain community will rally to protect this ideology with the same vigor that it pursues lucrative Ethereum mining experiments.