should have done this a long time ago
Last year as part of our COaTI program, I set up an account with ifreebusy.com to demo sharing free/busy information, but it wasn't until just today that I finally figured out where and how I should be using it.
Often, when we're doing a COaTI, I find that I need to schedule calls with people who are far busier than I am. What I've done in the past is to ask that they send me a couple of times that are good for them, and then I pick a time that is also good for me. What I should be doing is asking people to check out my public free/busy calendar and tell me when they want to talk to me based on the calendar.
So, starting today, I'll be experimenting with how well this practice actually works. We've got a COaTI starting in about 2 months, so I'm sure I'll get lots of chances to use it.

