This is a fairly straightforward view to generate iCalendar (.ics) files, with a unique UUID, a proper filename, and the basic fields needed to export an event from a public calendar (using the django-events-calendar app). While it can certainly be extended and adapted, it works very well as-is.
In the last few days I spent a lot of time trying to find a library or repository of some kind that could help me generate the required DAYLIGHT and STANDARD components of ical VTIMEZONE blocks. Since I couldn't find anything, I cobbled together this snippet to poke around in pytz timezone information and output the bare minimum I needed to make my ICS files compliant and useful (DST transitions for this year and the next). I promise it's (superficially) tested against "real" ICS files, but that's all. UPDATE: Thanks to @ariannedee for a much improved version (see comment for details)
This code publishes an iCal file that can be subscribed to in Google Calendar. They change the way they interpret iCal data occasionally, so this may break, I'll try to keep it up to date. There is some crazy string replace stuff going on there, I haven't yet convinced vObject to format things properly. Feedback welcome. *Note: this works for my existing feeds, but if I add a new feed to GCal, the timezones are incorrect, I'm working on that.