Optical rectification in lithium niobate and semiconductor nonlinear optical materials, utilizing the tilted-pulse-front technique, has become a versatile source of intense single- and multicycle THz pulses. Novel approaches recently proposed, and some of them demonstrated, are promising to scale the technology to unprecedented field strengths by enabling uniform interaction length for THz generation across a large beam. The generation of continuously-tunable, narrowband THz pulses from phase-locked multi-millijoule femtosecond pulse bursts by optical rectification is demonstrated.