"Changing"/"cloaking" a file extention

[PoorDoggie]

Is there any way I can have a php file with a jpg extention?

The script makes an image basically, and I just want that one php file to be accessed by typing index.jpg instead of php.

Is there a way of doing that in htaccess or something?

Thanks
Tom

Don't worry, I found out, rewrite rules in htaccess docs do it well enough!