in reply to I usually boil water for tea using a(n) ...
I was a kettle-on-the-burner guy (it's just boiling water after all), until my sister bought me one of the fanciest electric kettles I've ever seen.
I've become a convert. It has variable temperatures (in degrees F it has pre-set buttons for 175, 185, 195, 200, and 212, which are supposed to be the ideal brewing temperatures for green, white, oolong, french press they snuck a coffee in, and black teas). It has mL markings on both sides of the kettle for right and left handed people, and it's just all-around geek-friendly.
Breville variable temperature kettle
Now I'm experimenting with loose-leaf teas...