I use Google Calendar, but only for myself. I haven’t worked in an environment that has shared online calendars. I think it could be useful for teams, across teams, to find out where people are, but there is the issue of people actually *using* it correctly. So I don’t really have a lot to say about GCal. It’s a calendar.
I’ve been trying out Evernote for about two weeks now and I think it’s really handy. Especially if you have an iPod touch, which can only go online if there’s wifi around, and you want to sync stuff to read offline. It’s easy, it’s intuitive, I’ll definitely keep using it. I’ll have to have a look and see how it can be streamlined/kept clutter-free, but so far, it’s been a really useful tool and definitely one of the more exciting Things.