I just came across a new feature in iGoogle that allows you to share tabs with others. This has the potential to be very useful if a school implemented iGoogle as a student start page or "virtual planner." Instead of trusting students to put useful gadgets on their start pages, you can give them each a uniform template which they can then customize.
I posted a screencast of how to create the template on my blog. If you're not familiar with iGoogle, I would recommend that you watch the video below. You might find something useful for yourself or your students!
I agree iGoogle certainly has value. It is one of my personal organizers. An alternative in schools would be to make outlook accessible to students as it is to my colleagues.
Are you referring to Outlook Webmail? Do you outlook web is comparable to an iGoogle page? From my use of Outlook Webmail I don't recall a whole lot of customization options.