I just found something interesting, if you know what cryptocurrencies are and you already have a blog with plenty of posts. Quite easy in fact, the only thing that you need to know is that you can copy/paste your old articles from your blog, if they are original and made by you. They are checking that, but if you own them, then there is no problem.
The website is called Publish0x, a blogging platform, and the easiest way to get crypto is to select BAT (Basic Attention Coin) to be paid and to send them at the end of every month to a Coinbase account. You will need to select the specific BAT wallet address from your Coinbase account and to sent them manually at the end of every month. You can publish up to 5 blog posts every 24 hours.
As a side hustle, using Brave Browser you can also gain free BAT, via little adds. I found this browser alright, working quite fine, and i often use it in conjunction with DuckDuckgo search engine to find some results that are different than Google (unbiased, i mean).
In a month you can make anything between 30 and 300 BAT (BAT value today 28/2/2020 is 0.21USD, so it is like £5-50). I have the maximum ads setting on Brave Browser and i got around 60 ads in the last month. You will not get instantly rich, but you will learn about cryptocurrency alternatives to Bitcoin and there are few interesting trends at the moment. Publish0x is at the moment the second rated blog platform at the profit value after Medium, and they will keep your posts in the game forever (at least this is what they claim), so if you have very interesting articles, they will potentially get you paid for years to come. The thing is that once you uploaded 100-200 blog posts, the payments go up quite nicely. So it is like 30 days = 150 posts and then you can forget about it. Real passive investment. Just check monthly to transfer the coins from Uphold wallet to Coinbase.
If you don't understand any detail, ask me, I will gladly help.
Disclaimer, some links are referral (so we will both get a small bonus, like £5-6 each for Coinbase, for example).