Image Steganography

Just as a little insert in between waiting for for my bluetooth usb, I decided to add this little tidbit. This could have just as easily been found on Google, but here it goes. Say you want to send a file to a friend, that you don't want out in the open? How can you do this? Encryption? Yes, but then they have to have a decryption tool. Here's a quick way to do it(on windoze). First, we take the file we want to hide, and zip it up, we'll call it file.zip. Okay, now we download a picture, we'll name it img.jpg. Okay, now, we'll hide this file inside our picture. Image steganography. Here's the windows command to make this easy:
c:\>copy /b img.jpg + file.zip newimg.jpg
Now we have a new file called newimg.jpg, if we open this file, it looks identical to the img.jpg picture we had. But if we look at the filesize, it is a bit larger now isn't it? That is because our zipped file is now inside of it. Let's see if we can get the file out. Using winzip or winrar we open the newimg.jpg file as if it was a normal zip file, and voila. We have our hidden file :D Have fun with this information, and don't do anything I wouldn't do ;)