Making money strictly with computer hardware is now possible since the advent of cryptocurrencies. Here is a list of ways you can use your hardware to earn money !
I will keep this list updated when I found new cool stuff.
Spare graphic cards
1. Mining a variety of cryptocurrencies
You have in your hands a device that could mine almost all cryptocurencies at the fastest rate achievable by generic computer hardware. There is ASICs (Application-specific integrated circuit) that can mine a lot faster, but you don't find that in normal computer.
Since your spare graphic card may not be the most recent and fastest one, I would suggest you don't mine most popular cryptocurrencies, check coinmarketcap.com and spot one that is less popular, less mined and there is chances you could mine some units of that crypto.
1. Mining Monero coins
Normally, mining cryptos with CPUs is too slow to be viable since graphics cards has surpassed them. BUT ! There is cryptos that are specifically designed to not be faster to mine on graphics card. They are designed to be mined on CPUs ! Thanks to the CryptoNight algorithm. One of them is called Monero and is currently the most popular, worthing as much as 255$ each. I would suggest you mine this one.
1. Mine cryptos using your hard-drive !
There is this coin called BurstCoin that is designed to be mined using hard-drives. Its based on a concept called "Proof of Capacity", and instead of calculating millions of hashes every days, you calculate hashes only once in the begining during a process called plotting, then those hashes will be reused when mining. The result of this is a huge energy efficiency rate boost compared to normal "Proof of Work" cryptocurrencies ! Which also mean : lower electricity bills for you to operate, awesome.
2. Be part of a cloud storage platform
Storji is a platform where you can rent your available storage space in exchange for a tiny amount of a cryptocurrency called STORJ. This platform makes the bridge between users who want to store files on the cloud and those who have spare disk space available.
As a customer, you pay for storing your files in the system, which will then be shredded into tiny pieces that are distributed across multiple nodes.
As an hard-drive renter, you'll receive thousands of those tiny chunks of files that will be saved into your disks. You'll then receive STORJ coins in exchange for that service you provide (based on the total amount of those tiny pieces you store for X period of time).
The way it's build, you cannot open the files you store and see what's inside because you possesses only a part of each files. And if one day you decide to stop renting your drives, the system has copies of your chunks on other nodes, so the file will still be available completely for the customer. Pretty cool right?
Spare complete computer
1. Host your website / blog
If you run a small website (or wants to), it could be hosted at home for free on an old computer ! Any decently old computer would be able to withstand small to moderate traffic, specially when your website/app is mostly a frontend app !
On that website you could also install a crypto miner from Coinhive that would mine Monero using the CPUs of your visitors. This way you would save on hosting AND make extra money.
And/Or install ads from AdSense or other ads networks.
The things you'll have to do are : forward port 80 from your router to your computer. You would also need a static IP to point a domain name to your server address, but I already wrote an article on how to fake having a static IP address
without paying for one. And that's it. It's also a pretty nice feeling to have a presence on the internet while being self-hosted !
If you have any other ideas, tell me in the comments below and I may add it to this list ! :)