For those of you using Apple’s iCal in conjunction with Google Calendar, here are two great ways to keep them in sync with each other:

Spanning Sync will do a two-way sync with iCal either manually, or at scheduled time during the day. It installs as a simple System Preferences pane - all you need to do is provide your Google Account login information, and Spanning Sync does the rest. The only downside is that the program costs $25 for a one-year subscription, or $65 for a one-time purchase. $25 a year just seems like too much for such a simple service as a calendar sync.

On the free side of things, GCALDaemon is an open source, Java based program that essentially does the same thing as Spanning Sync, although it supports Windows and Linux as well. While GCALDaemon lacks the hassle-free experience that Spanning Sync possesses, it is a good alternative for people who are not willing to throw down $25 a year.