Heat that comes up through the floor instead of blowing out of a vent. It is quiet, it is even, and in a garage or a basement it is the difference between a room you use and a room you avoid. New installs, additions, and repairs to systems already in the ground.
The cheap moment to put heat in a floor is before the slab is poured. After it, the options are a floor build up that costs you ceiling height, or nothing at all. If a pour is anywhere in your plans, even as a maybe, it is worth a conversation first. This is the one job where calling early genuinely saves money rather than just sounding like it does.
The other thing worth knowing is that in-floor heat is slow on purpose. It warms the mass of the floor and the floor warms the room, so it does not respond in minutes the way forced air does. That is exactly why it feels so even, and it is also why it prefers to be left at a setting rather than turned up and down.