For presentations it is always good to have nice looking and readable fonts. Usually I publish my presentations as PDF on Slideshare. Because fonts are embedded in the PDF document they should be free to use. I have been looking around for quite a while and have tried various fonts. At the moment I use the following set of fonts.
|Calluna Sans||Body text (Sans-Serif)|
|Calluna||Title, quotes (Serif)|
|Architect's Daughter||Notes (Handwritten)|
A collection of free fonts is available from Google web fonts. Inconsolata and Architect's Daughter fonts are in there. The complete collection is available as a mercurial repository:
hg clone https://googlefontdirectory.googlecode.com/hg/ googlefontdirectory