  Over the past two years, we used a series of GBT observations to uncover at
least 33 millisecond pulsars in the globular cluster Terzan 5 located in the
Galactic bulge. We now have 32 timing solutions for the pulsars which give us
precise positions and dispersion measures (DMs) and indicate that the DMs are
dominated by variations in the integrated electron density along the slightly
different sight lines towards the pulsars. At a distance of ~8.7 kpc, angular
separations between the pulsars range from 0.4"-100" and correspond to
projected physical separations of 0.01-4 pc, giving us a unique probe into the
ionized ISM properties on these scales. Our measurement of the DM structure
function toward Terzan 5 is not inconsistent with Kolmogorov-like electron
density fluctuations in the ISM on scales ranging from at least 0.2-2 pc.
