Hi,
Nearly a yewar ago there was a report that a US School had given out Macs that had software on them that allowed the School to access the computer and the Camera.
They claimed it was so they could see who had any computer that was stolen.
I don't remember if the story actually said if any were stolen.
It did say that students got to find out and the School was in a lot of trouble for taking and storing pics, mainly of students in thier bedrooms.
I don't remember if anyone said the light came on or not.
I don't think it is going to be any sort of hacking.
Things to exclude.
Some Web Sites can access the camera via the Flash Plug-in.
This normally causes a Pop up to appear where you have to specifically Agree to Allow access. However there is also a Remember button.
It is a long time since I saw someone code a page that accessed the camera without asking (whether that is Adobe changing that feature or actual Coding I am not sure)
There is also a Google Video Chat Plug-in for Macs so they can chat via the Google Mail Web page Chat option.
I had used this very little and can't say that I can remember if it asks for Permission.
However you don't say you found a Video Chat Invite in a Google Chat
Face Time on a Intel Mac and iChat on any both do a partial Login at the Computer Start up.
In iChat's case this will start the iChat Up if someone sends you an Off Line IM (it does depend if you have reset the default Accept to be Off - normmaly by a Message from AIMSysMessage asking if you want to receive more - answering No to the IM turns it Off)
In Face Time's case any Incoming call will start up Face Time.
The Beta seems reluctant to show a Window but the camera is then Active.
I do not have the App Store version and don't know if the Preferences can be set to only accept calls when fully active.
Sticking somewhat with Web Browsers there are apps that can be set up to detect movement linked to the Screen Saver being active (or not) and loading it to a web site (on the Mac or External).
See EvoCam and SecuritySpy in the Nanny cam section of this page
Also consider everything else on that page.
iMovie, Quicktime that you already have and any of the Add-on and apps listed.
Remember the list is not exhaustive.
For instance Comic Book bundled at one time with soem Macs can access the camera for Snap Shots.
System Preferecnes > Accounts > (Any Account) > Login Pic
This can access the camera for Snap Shots if set to Change the Pic
Depending what items you have in System Preferences > Sharing and in some cases additional Access Passwords you may have a point of Access.
Screen Sharing can be accessed without an incoming password over VNC This would tend to mean that your routiung device is forwarding that port (normally 5900) to your computer - OR - you are connected directly to the internet such as a Cable modem.
Any person making use of this would have the same access to the Mac and its apps, System Folder structure that you do.
Most of the Posts that have said someone has reported similar to you (and reported back) have tended to say that a fault was found when they took it to a Store.
The Internal iSIght is a USB device.
The OS numbers the devices you have so it "knows" which one the apps and other softare are trying to contact and use.
It is know that sometimes the Mac loses track of which device is which.
The camera may have been triggered when it should have been an External Hard Drive or other device.
Restarting the computer will normally sort this.

8:47 PM Saturday; May 21, 2011
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