I've been using one of these for years at work.
I'm an electrician and find it invaluable for checking fuse boards for hot circuits, heating systems for correct operation, underfloor heating manifold balance etc.
Just point and press. Or lock it on and wave it about a bit.
Now however I have to get a new one, 'cause my wife's nicked it.
She's found it's great for checking baby's bottle temperature, cot temperature, baby's hands etc.
While I'm at it I'm getting one for her friend too.
Might as well get a spare 'n all. . . . . .