RTGs are fun and fine for many fringe purposes. At the milliwatts-to-watts scale, the amount of radioisotopes makes them way too risky to use in commodity electronics. Fine for fringe, remote power, but not great for like laptops.<p>For reference, the amount of Strontium-90 in one 250 Watt thermal (~10 Watt electric) RTG could give out about 63 million certain death 10 Sievert doses if people were to ingest or inhale all of it.