Internet security experts won a key battle against spam email on Saturday when they were finally able to disable a huge "botnet"–a network of hacked public computers. That network was called "Grum," and it had been used to distribute half of the world's unwanted emails. Its servers, based in the Netherlands and Panama, were first attacked on Wednesday. After Grum's unknown managers restarted the servers using machines in Russia and Ukraine, authorities again attacked, shutting them down for good. It's unclear if the victory will keep more spam out of your inbox, as new botnets aren't difficult to start.