application on startup?

How do you set certian applications to start when the computer boots. I would like to start up my IM and IRC clients (adium and colloguy).

In system preferences, then go to accounts and click login items and click the plus sign and you can add whatever.

Is there another way? I have set up Mail and Cal to open on startup and now I want them off. I went to accounts and login items and those are not checked. I don't remember how I set that up.

Right-click on iCal or Mail and select or unselect as in screenshot