There are few techniques you could use that don't affect the visitor experience of your own. - Detect referrer and return a script that has a warning - Rotate

There are few techniques you could use that don't affect the visitor experience of your own. - Detect referrer and return a script that has a warning - Rotate your script filenames so those hotlinking will soon realise they will need to host it themselves - Use a CDN yourself and don't encourage them to hotlink - Slow down the request For those hotlinking, consider: - You can't trust the source of the code - You can't trust that the code will always be there and it will load quickly - You can't trust the contents of the code may change and break your application If you want to be sinister to those hotlinking you could: - Redirect the user (as others have noted) - Display any message to the user - Steal data from the user who is using the site hotlinking - Inject your own adverts into the target web page - Make the web page do the Harlem Shake