I want to build a small transmitter that will broadcast on all frequencies used by cell phones, and make it directional if possible. When activated, this device will produce a loud, high-pitched, migraine inducing tone straight into the ear of the goddam fucktarded SOBs who drive like they have their heads up their asses while talking on the fucking phone while they should be paying attention to the road.

I am dead serious about this.

you can cut into the mobile phone band and listen in on, transmit into, and even take over phone details and use them for your own needs.

i don't know how it's done, but i know it can be done because i know people have been arrested for it.

Bluetooth is especially vulnerable.

indeed. i have seen software (linux software) that can connect to a phone via bluetooth, and take the phone over completely, performing many functions (eg - make calls) via the computer interface.

my friend has software on his pc to do it the other way round... control his pc using his phone via bluetooth. pretty nice actually. works as a great media remote

Yes, but it is vulnerable to complete control externally by anyone with a bluetooth device

i thought i said that... or are you referring to other bluetooth devices such as bluetooth keyboards and such?

of course many phones set bluetooth passkeys, and unless the same passkey is entered at either end, a connection or "pairing" cannot be established. (of course a novice would stop here but... well... )

I know in some cinemas they have an anti mobile phone device. Essentially it blocks the carrier wave length in a radius around itself.
Would love to get one myself.
The best I can think of is a water pistol to squirt through the window at em.
Or do as an old buddy of mine used to do, carry around a bag of potatoes as ammunition.

there is also a coating you can get on put on windows, alot of the time used in offices and now in alot of fast food outlets and restaurants that deadens mobile phone signals. it's used to keep wifi inside the building and make it harder for people to gain access to their networks from outside the building.

It's completely possible. Though, I would suggest doing it in some way that allows you to target a specific phone. You could implement GPS in some way to home in on a person's phone. Most phones run some sort of Java OS, and there's all kinds of way to hack Java applets...