There is no way to block images from being downloaded, even with javascript. PHP is a server-side language, so it doesn't have control over the client enviornment. If you don't want images to be downloaded, better to not put them up. Any Javascript hacks are easy to get around by either disabling javascript, clicking the view source button, or better yet, going directly to the browser cache. Personally I am annoyed by such hacks!
Regards,
Rich
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The Spicy Peanut Project
http://www.spicypeanut.net
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