Crazy idea: an browser extension a user can install which downloads images as they come across them in their browser and uploads them to something distributed - perhaps built on top of IPFS? Users could choose which domains it would be active on. The network could be split up by either domain or topic (say, people interested in diagrams of space which might include several domains/sites).
The problems with putting that kind of data in any sort of distributed service are that:
1) It depends upon enough users being able to consistently contribute a lot of storage to the system. It turns out that this is hard. Casual users are actually a hindrance, because they'll suck up a bunch of bandwidth trying to replicate data, then drop out of the swarm forever.
2) The service will inevitably be used to host illegal pornographic content. Without some sort of centralized control, there's no way to stop this, making participation legally problematic.
Just thinking out loud here.