Replacing ads reminds me of the eye tap AR stuff by Steve Mann
https://news.ycombinator.com/item?id=44406552
These days he's helping to remediate polluted waterways
https://cottagelife.com/general/this-toronto-professor-took-...
These days he's helping to remediate polluted waterways
https://cottagelife.com/general/this-toronto-professor-took-...