  We present preliminary results from the deepest VLBI observations yet
conducted. VLBA+GBT 1.4 GHz observations of a region within NOAO-N, reach an
r.m.s. noise level of 9 microJy per beam. Three sources are clearly detected (>
7 sigma) within the inner 2 arcmins of the GBT primary beam, including two
sub-mJy sources and the ``in-beam'' calibrator. In addition, by tapering the
data, we map out a much larger area of sky, reaching well beyond the half-power
point of the GBT primary beam. An additional 6 sources are detected in the
extended field. We comment briefly on the scientific motivation for even deeper
and wider VLBI surveys, and note that the summed response of sources in the
field will permit self-calibration techniques to be employed in any region of
the radio sky, including so-called ``blank'' fields.
