Our wireless one only worked sometimes, which isn't terribly useful. I unplugged it and put it in the garage where it, at least, is guaranteed not to work.
Frankly, I'd rather not be disturbed, it's not like people turn up on spec unless they're trying to sell me something, are religious loons of assorted flavours, political types who somehow get past the bears, or a delivery (in which case they're in the van and sailing off down the street in the 5 seconds it would take me to answer the door).
In theory I could activate the security cameras on the drive and porch and that would ping me when someone approaches, in practice I can't be arsed unless I am specifically expecting something or it's one of those days I anticipate a Viking raiding party.