o prevent attacks. "Often, sub- scribing to a Web site results in an automatically generated e-mail message asking the subscriber something like, 'Do you want to subscribe to our Web site?" he notes. "We propose that Web forms be written SO that the forms do not cause a message to be sent to subscribers at all. Instead, the form would prompt subscribers to send their own e-mails confirming their interest in sub- E-MAIL "CLUSTER BOMBS" scribing. This would prevent the Web site from being abused in a cluster bomb attack." Menczer conducted his research with Markus Jakobsson, principal Research Scientist at RSA Laboratories, a computer security firm, located in Bedford, Mass. Funding for the study came from an National Science Foundation Career Grant and the Center for Discrete Mathematics and Theoretical Computer Science at Rutgers University. Chapter Energy to Go- Power Generation Given the number of portable electronic devices flooding the market, the need for cheap, portable, and quickly renewable electrical power sources has never been greater. Yet, despite researchers' best efforts, today's portable power sources remain stubbornly bulky and expensive. 8.1 NEW MATERIALS New materials promise to extend the performance of conventional battery technologies while opening the door to new types of power sources. Scientists at the U.S. Department of Energy's Sandia National Laboratories in Livermore, California, are among the researchers investigating promising new power-storage substances. The scientists' initial work appears promising. Sandia's researchers have developed a new class of composite anode materi- als-composed of silicon and graphite-that may double the energy storage capacities presently possessed by graphite anodes. The anode is the negative electrode-or battery area-where electrons are lost. The breakthrough could lead to rechargeable lithium ion batteries with more power, longer life, and smaller size. The marriage of silicon and graphite may improve the capabilities of commercial graphite anode mate