Dear Katherine,
I expect you already have steemit.com under consideration as a potential revenue source for the guardian. Steemit is a blogging block chain where posters earn cryptocurrency - steem - through their content.
A poster was talking about it this morning in terms of the New York Times - you would open an account for The Guardian, mirror posting articles which are upvoted (earning rewards), and similarly for comments that are made by other posters.
It's a young site, ranked about 1,500 with Alexa.com, has about a million accounts globally of which 60,000 are active. It has some teething problems, but also huge growth potential.
I've been a member for just under a year, I'm still learning how it works, but I was interested in the potential for financing investigative journalism. (The trending page is a tragedy - but your influence might help to change that if you were interested in joining the platform).
Best wishes,
Shani