  We argue that the Milky Way (MW) contains thousands intermediate mass black
holes (IMBHs) and minihalos with a fraction of IMBHs still being enshrouded in
extremely dense mini-spikes of dark matter (DM) particles. Each containing
$10^6\msun$ of dark particles and no baryons in a sphere of 50 pc radius, the
minihalos are dense enough to survive the Milky Way tide with the nearest
minihalo within 2 kpc from the Sun. The IMBH is formed off-centre in a minihalo
by gas accretion, and its growth adiabatically compresses a finite density of
surrounding dark matter into a $r^{-1.5}$ mini-spike. Some IMBHs recentre on
their minihalos after dynamical friction, and some IMBHs are ejected by birth
kicks. Detectable by GLAST, the mini-spikes and minihalos should stand out the
background and dominate the neutralino annihilation in the smooth MW and
satellite galaxies. If they are the unidentified EGRET sources, upper limits
can be set on the branching ratio of neutralino annihilation. The supermassive
BH of the MW, if orginates from an IMBH, is also likely enshrouded with a
mini-spike.
