I'd like to set up Linux to cache some commonly requested URLs so that it doesn't have to go out to the net to get them every time. This would be a system-wide URL cache, not just in a particular browser. For example, a program might request http://www.w3.org/TR/html4/sgml/loosedtd.html a few thousand times per day. There are many other URLs I'd like to cache as well.
Is there an app for that?