If I want to make a sensor network I will usually use the arduino board with the sensors connected by jumper wires to the arduino and then implementing a radio/wireless connection between my arduino and a web-server or other arduino board depending on the case. This is the most common scenario, I think.
What I'm looking for is that if I want to distribute sensors in different sites at my home (let's see in each room), then according to the previous scenario, I would buy an arduino for each sensor, sense I cannot connect sensors to the arduino without jumper wires.
My question is if there any kind of sensors that have builtin powering system and wireless connectivity so it will be easy to distribute it in different places without connecting it to the arduino by jumper wires? or if there's any other solution.
Thanks in advance.