If you need a lightweight and easy to use calendar app for your desktop, look no further! elementary's smooth and clean calendar app (Maya, now renamed "Calendar") is back.
Your eyes. Feast them!
Calendar is fast, easy to use, and in my experience so far, seems to be relatively stable (though it's still a work in progress so expect bugs). Currently missing are any options for online syncing, though according to blueprints, such features are on the way.
Seeing as this is bleeding-edge software, the usual warnings apply:
So, all jokes aside, here's how you can get Calendar on your system:
sudo apt-add-repository ppa:elementary-os/daily
sudo apt-get update
sudo apt-get install maya-calendar| or search for it in the Software Centre