I needed to build an offline calendar in jQTouch for a project and found this particularly nice-looking jQTouch iCal project by Bruno Alexandre. Unfortunately, it required a server connection.
A day later and I've pulled the thing apart, refactored and rebuilt into a shiny jQTouch extension (still using the original project's CSS). It's built for Mobile Safari but still looks good in other webkits.
Grab the code from the GitHub repository
