  We report the discovery of significant localized structures in the projected
two-dimensional (2D) spatial distributions of the Globular Cluster (GC) systems
of the ten brightest galaxies in the Virgo Cluster. We use catalogs of GCs
extracted from the HST ACS Virgo Cluster Survey (ACSVCS) imaging data,
complemented, when available, by additional archival ACS data. These structures
have projected sizes ranging from $\sim\!5$ arcsec to few arc-minutes
($\sim\!1$ to $\sim\!25$ kpc). Their morphologies range from localized,
circular, to coherent, complex shapes resembling arcs and streams. The largest
structures are preferentially aligned with the major axis of the host galaxy. A
few relatively smaller structures follow the minor axis. Differences in the
shape and significance of the GC structures can be noticed by investigating the
spatial distribution of GCs grouped by color and luminosity. The largest
coherent GC structures are located in low-density regions within the Virgo
cluster. This trend is more evident in the red GC population, believed to form
in mergers involving late-type galaxies. We suggest that GC over-densities may
be driven by either accretion of satellite galaxies, major dissipationless
mergers or wet dissipation mergers. We discuss caveats to these scenarios, and
estimate the masses of the potential progenitors galaxies. These masses range
in the interval $10^{8.5}\!-\!10^{9.5}$ solar masses, larger than those of the
Local Group dwarf galaxies.
