OK, so I did this for a bit of fun but thought I would share here.
http://www.blockchainsudoku.com is a visual representation of the blockchain. Each cell represents one wallet. The single-digit for the cell content is taken from the first digit of the wallets received Satoshi. For example, if 400 Satoshi are sent to the wallet, a 4 will be displayed. If 5876433 Satoshi were sent, a 5 will be displayed.
The grid is updated every 5 minutes, but as it is a representation of real wallet values, you can, of course, check out the current value using more up to date sources.
The source code can be found here -
https://github.com/blockchainsudoku/blockchainsudokuI think the challenge beyond a normal Sudoku grid is that more than one person can be trying to complete it at a time. Hence why the Sudoku grid render makes use of the first digit. If it gets messed up at the lower end, people can correct it with a larger value.
Not sure how much if any interest there will be in this, but if it does result in a profit, I will donate a proportion of the profits to Ocean Cleanup charities. Don't expect any funky graphics or even CSS, I wanted to keep it as raw and basic as possible.