Not enough is known yet about 'dark flow' which is the apparent motion of all matter in the known universe toward a possible, and impossible, gravitational mass outside the universe.
This article mentions Alexander Kashlinsky, a lead researcher for NASA, as mentioning the possibility of extra-universal matter. The report is not undisputed.
The Wilkinson Microwave Anisotropy Probe (WMAP) data has provided a new look at the universe from the point of view of the energy still visible from the postulated Big Bang event. However, this particular new look is confusing. Everything in the universe seems to be moving against the background radiation, all in the same direction and at a speed of 0.003 c, which is incomprehensible in the existing isotropic rules assumed by none other than Einstein himself when he developed his Theory of Relativity. So, all cosmological bets are off. However, 'dark flow' might be useful in comprehending where our economy is headed. Yes, it might be gravitationally attracted to a huge gravitating mass outside the universe.
I wrote this myself, including spelling and grammar.