Guys, your problems with mac can easily be fixed. Use a usb mouse and keyboard and voila! 2 mouse buttons and a numpad. Also, don't say "macs haz sucky grafix cards" because my dad's macbook pro can run GMOD on highest settings without lag.
It doesn't take a very powerful graphics card to run source games on max settings.
With full AA?
I'm on a laptop and I can play Portal at absolute max settings (AA and AF as well) and never dip below 50 fps.