Paul Woods at design firm ESPI notes that the team there hardly ever uses its Adobe Creative Suite tools to design web sites, presentations, or other design-needed items. Instead, everybody turns to Apple's Keynote, part of the $129 iWork suite.
It's not so much that Keynote does everything well, as Woods is honest about the limitations, including the lack of robust hot keys. But the point is that, for many projects, Keynote's wire frame tools and wide range of export formats can get the job done quite well, once you learn how to use it without assuming it's just for slides.
ESPI at work: The power of Keynote [Edenspiekermann]