$100? hmm this price may not be that bad though, considering the display seems to be the most expensive aspect and I'm not finding a similar price/size on Amazon.
One thing I want to learn/address personally is a charging circuit so I'd rather build it myself. Still it is nice to know this is out there ready to go.
Also I have to use these ESP01's I bought haha. The code itself I imagine wouldn't be difficult eg. an http get request firing at whatever interval to your own local/remote endpoint. Would have to see about the ESP driver part to display to eInk.