I'll forward your picture to Penn State entomology. It may take a while to get an answer, but I'll email you as soon as I hear from them.
Here is the response from Penn State:
hat appears to a longlegged sac spider, either Cheiracanthium inclusum or C. mildei. Of the two, Cheiracanthium mildei is the species most often found in homes, so if it was photographed indoors it's likely that species. Both species were thought to cause necrotic lesions, but there have never been any recorded cases of necrosis in humans and the original animal studies were flawed, so they're not considered to be of medical concern now. That being said, both species will bite if mishandled and the bite can be pretty painful. We have a fact sheet about them if you need additional information.