I came across the Philadelphia Architects and Buildings while browsing UPENN‘s website. Here is a blurb about the site:
The Philadelphia Architects and Buildings database provides authoritative information on three centuries of Philadelphia buildings and designers. PAB incorporates data and images from the collections of more than 25 Philadelphia-area repositories. The database is added to and amended daily, and additional building and biographical information is welcomed through our user feedback.
I found out that the building I live in is a registered Historic Place. I am not sure what happened here, other than this is my first residence in Philadelphia, but I am sure it was something very cool.