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THIS WEEK IN edited by Stella Hurtley and Phil Szuromi Fast Light Switch Seek, Fortify, Then Destroy Certain organic salts form one-dimensional (1D) or 2D electronic bands that are partially filled and that can give rise to electronic and magnetic properties such as superconductivity or ferroelectricity. Chollet et al. (p. 86) examined the organic salt (EDOTTF) 2 PF 6 , where EDO-TTF is ethylenedioxytetrathiafulvalene, which forms a quasi-1D band that is one-quarter–filled with hole carriers. This material displays a metal-to-insulator (M-I) transition near room temperature that arises from structural changes that lead to charge ordering. The authors find that this M-I transition can be brought about very rapidly (in a few picoseconds) after photoexcitating only a very small fraction of the molecules within the crystal (about 1 in 500) at temperatures near ambient. This phase transition appears to be driven by a coherent phonon generation process caused by the interaction between the electrons and the lattice. Such properties may prove useful as an ultrafast molecular switch. In clinical trials, “anti-angiogenic” drugs, which are designed to destroy the blood vessels that feed tumors, have limited efficacy when administered as single agents. However, when provided as a combination therapy, they enhance the efficacy of conventional cytotoxic drugs targeting tumor cells, even though the destruction of the tumor vasculature might be expected to impede drug delivery to the tumor. Jain ( p. 58) reviews evidence supporting the counterintuitive notion that antiangiogenic drugs initially fortify, rather than destroy, the tumor vasculature, thereby improving delivery of cytotoxic drugs to the tumor. If further substantiated, this hypothesis would have important implications for the optimal dose and scheduling of combination cancer therapies. Pentagonal Columnist