  We point out that if the lightest supersymmetric particle (LSP) is a
Higgsino- or Wino-like neutralino, the net effect of coannihilations with
sleptons is to increase the relic abundance, rather than producing the usual
suppression, which takes place if the LSP is Bino-like. The reason for the
enhancement lies in the effective thermally averaged cross section at
freeze-out: sleptons annihilate (and co-annihilate) less efficiently than the
neutralino(s)-chargino system, therefore slepton coannihilations effectively
act as parasite degrees of freedom at freeze-out. Henceforth, the thermal relic
abundance of LSP's corresponds to the cold Dark Matter abundance for smaller
values of the LSP mass, and larger values of the neutralino pair annihilation
cross section. In turn, at a given thermal neutralino relic abundance, this
implies larger indirect detection rates, as a result of an increase in the
fluxes of antimatter, gamma rays and neutrinos from the Sun orginating from
neutralino pair annihilations.
