This talk describes some of our recent work on pumped microfluidic networks for new classes of dynamically tunable fiber and integrated optical components. It presents two different types of devices. The first combines microstructured, or "holey", silica fiber with microfluidic plugs that can be tuned and pumped back and forth in the fiber using thermal pumps formed directly on the fiber surface.@footnote 1@ We present two examples of devices that use this microfluidic optical fiber design. One relies on dual-fluid plugs and long period fiber gratings; this component provides variable, wavelength-tunable attenuation for dynamic gain equalization in wavelength division multiplexed optical networks. The other uses fiber tapers; it provides a broadband variable attenuator that can be useful at add/drop nodes. The second class of system combines electrowetting pumps and recirculating planar microfluidic channels with fiber and integrated optical structures. We describe the fluidic and optical physics of these devices, and we demonstrate the performance of several different components that use this design.@footnote 2@ @FootnoteText@ @footnote 1@ P. Mach, C. Kerbage, M. Dolinski, K.W. Baldwin, R.S. Windeler, B.J. Eggleton, J.A. Rogers, "Tunable Microfluidic Optical Fiber," Applied Physics Letters, in press. @footnote 2@ P. Mach, T. Krupenkin, S. Yang, J.A. Rogers, "Dynamic Tuning of Optical Waveguides with Electrowetting Pumps and Recirculating Fluid Channels," Applied Physics Letters, submitted.