A null plugin for Mozilla (or other browsers using the Netscape plugin format, such as Konqueror) that I could set to be used for Flash files. It would avoid the annoying dialog in my local Mozilla, which doesn't have the plugin installed, and I could preload it over raptor's Mozilla so I don't have to put up with Flash animations.
I believe you can configure Plugger to behave this way. With modern versions of Firefox, the behaviour when you don't have a plugin is far less irritating. For the precompiled-Mozilla case, I've implemented a plugin filter preloadable library: killplugins.