  Weakly interacting massive particles (WIMPs) are among the favored candidates
for cold dark matter in the universe. The phenomenology of supersymmetric WIMPs
has been quite developed during recent years. However, there are other
possibilities which have not been discussed as much. One example is a
right-handed massive neutrino, which has recently been proposed in the context
of a version of the Zee model for massive neutrinos. This TeV-scale, leptonic
WIMP (or LIMP, for short) may at first sight appear to be essentially
undetectable. However, we point out that the radiatively induced annihilation
rate into leptons and photons is bound to be substantial, and provides a
conspicuous gamma-ray signature for annihilations in the galactic halo. This
gives a window of opportunity for Air Cerenkov Telescopes with ability to
observe the galactic center, such as the HESS and CANGAROO arrays, and also for
the GLAST space telescope. In addition, the contribution to the positron cosmic
ray flux is in principle detectable, but this would require very strong local
density enhancements in the dark matter halo distribution.
