Shp.JS is a JavaScript library used for reading and writing Shapefiles. More
info to follow.  Library is in its infancy, and contains numerous bugs/missing
features.  Library currently supports both reading and writing support, with
the exception of reading the projection file.

Library utilizes the ESRI JavaScript API, though de-coupling of the library
from the ESRI API is possible/planned.

Stay tuned for further updates.