hi AO's !!!

Well, i had this nagging curiosity of knowing that are there any known Image Viruses/ Trojans that can be embeded into .bmp, .jpg or .gif files ???

I feel this viruses/ Trojans if in existence will be really hard to detect and more over they will be so deceptive in nature. Imagine a virus embeded in porn picture !! If downloaded can cause a havoc with the computers.

Note : I used porn example only because that will be the really tempting picture to most of the people.

Waiting for replies.
Thanks in Adv.