Probably worth checking out hadron.cloud, a browser based AI blockchain. The mining is actually the contribution of CPU/GPU to common AI tasks like classification etc and can be run in a background tab without impacting browsing. There are however some implications yet to be tested e.g. network connection will be constantly open and close, on a WIFI network, this is probably OK but on a 3G network this is likely to cause battery drain, but still a very innovative use.