Office online - publish your calendar on the Internet
Did you know that you can easily share your Outlook agenda online using Office Online. It's free and it's simple.
Simply publish your calendar to the Internet (right click on the calendar in outlook, and Publish To Internet).
This is how it looks in my case (in Flemish) - where I have opted to show only the basic busy/available information. You can go for much more detail if you want, but I don't want people to know when my next appointment with the dentist is scheduled :-) I just want them to know when I available, so that they can book a meeting with me - without having to mail/phone to me 4 times... (of which 3 times they end up in my voicemail).
