  We study invasion percolation in two dimensions, focusing on properties of
the outlets of the invasion and their relation to critical percolation and to
incipient infinite clusters (IIC's). First we compute the exact decay rate of
the distribution of both the weight of the kth outlet and the volume of the kth
pond. Next we prove bounds for all moments of the distribution of the number of
outlets in an annulus. This result leads to almost sure bounds for the number
of outlets in a box B(2^n) and for the decay rate of the weight of the kth
outlet to p_c. We then prove existence of multiple-armed IIC measures for any
number of arms and for any color sequence which is alternating or
monochromatic. We use these measures to study the invaded region near outlets
and near edges in the invasion backbone far from the origin.
