These photos are of an assassin bug I found in Central Pennsylvania on June 18, 2004. Thanks to Edwin G. Rajotte, Professor of Entomology and IPM Coordinator at the Penn State Department of Entomology for identifying these photos.
From what I've learned about the assassin bug, it's a beneficial critter to keep around, as it eats aphids.
According to Jack Schultz, Distinguished Professor of Entomology at Penn State, this is probably a juvenile assassin bug.
How did the assassin bug get its name?
Schultz said, "Look at the photo closely. See the strong beak bent down under the head? The bug sneaks up on other insects, straightens it out in front, and jabs it into the prey. It then injects digestive fluids, digesting the victim 'in the shell', and sucks out the contents."
Some interesting reading on Assassin Bugs: