If you have more than one iDevice such as iPhones or iPads. No jailbreak required.
You simply plug one device in. Aim it where you want to see. Then you can view what that camera is aimed at from anywhere that has Internet connection (Wifi or 3G/4G) on your other device.
There are other great features such as motion sensor cam that'll not only notify you that it's detected motion. It'll automatically email the video to you.
The app is called Presence. To find it search for the fallowing in the App Store, "presence by people power". It's completely free. Download the app on all iDevices you'll want to use.
Register an account and sign into it on both devices (one for viewing and the other is used as a security cam).
Registering and signing in is just an email address and password.
Here are my devices I have registered. I'm using my iPhone 4 and my old iPhone 3GS. Set the device you want to use as a security cam to "Home".
Set the other device you'll be using to view your security cam as "Away".
Select your device on the Home one to turn on its camera. Then just select the same device on your other device to view the security cam.
On your Away device you can tap the small camera icon on the lower left. This will turn it into a webcam chat so you can be heard and seen from the Home device. Kinda like FaceTime without calling.
Imagine having the cam aimed at the door of your house. You'll see when someone enters it and you'll be able to actually talk to them. They'll just hear your voice and find you on the screen.
I also like the fact that you can control the settings of the Home device from your away device. For example you can switch the home device into motion detection mode. Or switch to front camera.
In my example my 3GS doesn't have a front camera. But if it did I can switch from front to back camera giving me two security cams.
When motion detection mode is turned on it'll watch for any movement in line of the camera.
When it detects movement it'll do two things. First it'll send a notification to your Away device to let you know. So you can open your app and view what motion it detected.
It'll also email you a short video of the motion it detected. Think about this. If it caught someone breaking into your home or stealing something. The short video could be evidence.
I did have connection issues a few times but I'm pretty sure they where the result of slow Internet connection. Overall I'm very happy with this app.
I can think of many useful ways to use this app. Such as checking on pets, a baby video monitor or just greeting someone when they arrive home.
I'll be going on a lot of trips this month so I'm so glad I stumble on this app. It's going to be great to be able to check on my house while I'm away. I hope you find it useful too.