In the market-farming community there is a tool called the Flame Weeder. There are a few itterations of it already out there by Farmers Friend LLC.
I’ve been waiting on an electric version. I feel as though FarmBot could be the inspiration for others.
How it works (in theory):
Round metal base with ceramic interior. Coiled nicrome wire circling the interior of the ceramic head. (it would basically look like a door knob) The nichrome wire has a 1400C melting point.
The theory is that the coils get so hot, that when they slowly pass over the thread-stage weeds, the plant cell walls burst from the water boiling and they die in a few minutes.
It is an alternative to using petroleum based weeders and it would be some kickass inspiration for countless innovators.