Sometimes I still use a PC, and sometimes it's on a machine with decent hardware graphics acceleration for OpenGL. When that's the case, I like to use Really Slick Screensavers.
Note that these were originally for Windows, but there are links to ports for Linux (I have found the Red Hat 9 rpm, which works just fine) and there are, apparently, Mac OSX ports of some, but my Mac just doesn't have the graphics grunt, so I haven't tried those.
Note that these were originally for Windows, but there are links to ports for Linux (I have found the Red Hat 9 rpm, which works just fine) and there are, apparently, Mac OSX ports of some, but my Mac just doesn't have the graphics grunt, so I haven't tried those.