What he came up with was an interesting hack that uses small movements of the mouse pointer to send data at up to 1200bps, or about 150 bytes per second. The way he did this was very, very clever.

[Jacob]’s sweet hack creates an arbitrary number of CAN “devices” inside the Arduino code, and can treat each one of them as its own serial data channel. The “N” in CAN stands for ...

Using an IoT SIM that works on cellular networks in over 100 countries, the Electron's basic data plan starts at $2.99 per month for 1 megabyte of data and 99 cents for each additional megabyte.