Question: I have a MacBook Pro with a touchpad, and the only way I can figure out how to use the right click in my remote desktop session is by plugging in a mouse. 

`Ctrl`-click (what I usually use for right click), doesn't work, as `ctrl` is used in Windows for other things. Is there an alternative?

Answer: 
Either using two finger tap, or two finger "click" (by pressing down on the touchpad).
This is kind of embarrassing, but the real problem was I didn't know how to right click with a touchpad on the macbook (it was still less than a month old). Update: You can do this by clicking or tapping with both fingers at the same time.