Our group is developing an optical approach to quantum computing in which the bits, or qubits, are represented by single photons.  Although logic operations are inherently nonlinear, they can be performed using linear optical elements combined with additional (ancilla) photons.  The talk will mostly describe some of our recent experimental results, including single-photon logic gates, memory devices, and quantum error correction.  The performance of these devices can be improved using the quantum Zeno effect, in which frequent observations to determine whether or not an error has occurred can prevent it from occurring.