Step 0: Sign up for foursquare if you have not already.
Step 2: Go to Park Slope, Brooklyn and make sure you are facing the window described above.
Step 3: Open foursquare on your mobile phone and check-in to the location called "LampSquare" to turn the lamp on or off.
All "lamp-ins" will be recorded on the @LampSquare twitter feed along with any comments you leave. Also, feel free to submit pictures or videos of your effect on the lamp to the LampSquare blog.