It's no iCal-killer, but I needed something to let me at least view my ical calendars from the terminal. At this point, other than bugs that can be traced to vpim (having to do with recurring events that hit the wrong days, e.g. leap day), it works. It's far from my first Ruby code, but it's my first public Ruby project.
That's the good news. The bad news is that it's definitely still rough around the edges, it isn't packaged in any way, and you'll have to install the vpim and ncurses gems to use it. Grab it from subversion at http://calterm.rubyforge.org/svn/trunk/ or start at the CalTerm home page.
This is sort of a preliminary announcement before I've figured out how I want to package it, so there's no release version.