EasyRes - EasyRes is a fast screen resolution switcher for Mac OS X with live animated previews.
Uxcel - The easiest way to learn UX/UI design
SwitchResX - SwitchResX is a tool designed to manage resolutions of all your monitors and HDTVs.
UX Challenges - Done reading about UX? Start doing it.
Screen Resolution Manager - Screen Resolution Manager is one of the robust and streamlined desktop applications that come with an easy way to adjust your screen resolution.
UI Coach - Become a better UI designer in 30 days