Simple project help

Ok guys so i got a mega 2560 and a sensor shield and my project is simple attaching jumper wires to all the pins in the shield with alligator clips at the end and my train of thought is that by connecting this alligator clips to different wires in different devices i can sort of "Tap" or "Hack" Given the right arduino coding of course into the device.???

An Example: An RC Car with the cover taken off and the original board still in it I can just clip the existing wires that lead to the steering servos and the motor with the alligator clips and with the original board still in place be able to control the rc car with the arduino and in a sence "Hack" It

Sounds simple enough. If you can also attach the alligator clips to an empty pizza box and turn it into a satellite TV with free premium programming, deal me in! :)

lol that was my next project!!! i cant decide on which pizza place though ;)

Clever. The CPU fan will keep the pizza hot, too.

I think that it can be done with the arduino to be able to "tap" into say another arduino robot and control it without modifying the original project

Given the right arduino coding of course into the device.

That's always the tricky bit - assuming everything you clip onto only has 0-5V signals.

Orleymtnez: with the original board still in place be able to control the rc car with the arduino and in a sence "Hack" It

If by this you mean that the Arduino will override the original control system then the two control systems would be fighting each other and whichever had the more powerful drivers would win. It might work, it might not. It might damage something, it might not. If you want to modify the behaviour of an RC car then I think it would make more sense to wire the Arduino to pairs of male/female sockets for the RC servo connectors and pass the signals through the Arduino so that your sketch has an opportunity to modify them.