  We present a successful inflation model based on $\lambda \phi^4$ potential
in which a Standard Model (SM) singlet inflaton $\phi$, with mass of around a
TeV or less, also plays the role of a weakly interacting scalar dark matter
particle (WIMP). The WIMP relic abundance generated after inflation is in
accord with the current observations. The spectral index $n_s$ lies within the
WMAP 1-$\sigma$ bounds, while the Planck satellite may observe the
tensor-to-scalar ratio, a canonical measure of gravity waves, which we estimate
lies between 0.003 and 0.007.An unbroken $Z_2$ parity ensures that the scalar
WIMP is absolutely stable.
