Shared calendars are great in iCal, but what if you want to share an iCal event with friends who don’t use the program? What if they don’t even have a Mac? Select the event you want to share in iCal, then drag it to the desktop. This creates an .ics file that can be opened easily in most calendar applications, whether on a Mac or Windows. You can then email this as an attachment, share it as a file on Dropbox or send it via instant messenger. And, by the way, you can do this with iCal to-do list items too.