This is an interactive 3D representation of the celestial sphere with pictures of deep space objects from my astrophotography hobby projected onto their true locations.
You may also be interested in a less interactive gallery of these images.
The Celestial Sphere
Background - roughly what you would see looking in a particular direction at night (see credits below).
Celestial Coordinates - grid lines show right ascension (RA - "longitude") in hours and declination (DEC - "latitude") in degrees. The celestial sphere rotates once every 24hr to keep objects at consistent coordinates sans parallax and real motion.
Ecliptic - the orange ring tilted relative to the celestial equator is the path the Sun takes through the sky every year.
Planets, Sun, & Moon - these are shown at their true positions, right now, and update in near real time.
Opposition - labels on the Ecliptic are the time of year that position is opposite the Sun, which is on the RA that crosses the meridian at local midnight.
Zenith - or "straight up" would be would be at the opposition RA plus the current hour of the day combined with the DEC equal to your latitude; Philadelphia is +45 latitude, and this page opens to a zenith view at midnight at that location.