repurposing old installed motion sensors

[back_ache]

I have an old dead alarm in my house left by the previous owner.

It itself is dead but what is interesting is it leaves my house covered by traditional wired motion sensors and the assoiated cabling.

If you you were in my place how would you repurpose these sensors and cabling in an interesting way?

[toscal]

You could use them for occupancy sensing or connect them up to a wireless alarm system. Most wireless systems allow for at least 2 wired sensors, plus they sometimes have modules to accept several wired sensors. I have successfully used door/window sensors which often have a pair of terminals to connect a wired sensor to them. The only problem is supplying the sensors with power. But as all the sensor cabling should be going back to a central unit then this shouldn't be too much of a problem, as you could use a single 12V dc supply (but check to make sure its 12V you need).