  Elliptic flow and Bose-Einstein correlations have been measured in Au-Au
collisions at $\sqrt{s_{_{NN}}} =$ 130 and 200 GeV using the PHOBOS detector at
RHIC. The systematic dependencies of the flow signal on the transverse
momentum, pseudorapidity, and centrality of the collision, as well as the beam
energy are shown. In addition, results of a 3-dimensional analysis of two-pion
correlations in the 200 GeV data are presented.

Nuclear Experiment