Capacitors are typically connected together in one of two configurations: either in series, or in parallel. Here we study a capacitor-within-capacitor (CWC). Simulations and experiments indicate that the overall capacitance of the structured cell may be made larger than an ordinary two-plate counterpart by at least 50%. Simulations also indicate that the cell's capacitance may be controlled by the gate voltage. Overall, this concept is deemed suitable for microfluidic sensing and possibly for energy storage elements.