As should be obvious from the design (I use the term “design” loosely here) of this website, I am a fan of 1) minimalism and 2) the Computer Modern font. To that end, I made a barebones Keynote theme which uses Computer Modern Concrete for everything. Here’s what it looks like:

Like I said–pretty barebones. Note, even, the lack of bullets next to the bullet points.

To make this work, you’ll first need to install the Computer Modern fonts. Once you’ve done that, grab my theme and throw it in ~/Library/Application Support/iWork/Keynote/Themes.