Font for Power Point presentation - (Jul/01/2010 )
I had an immunology lecturer who gave all of her lectures with comic sans for the font on the slides. AND she used multiple colours too. As a result "ban comic sans" posters appeared all over the department.
Worst. font. ever.
For presentations I usually use Trebuchet, because it's a standard font in Windows and loks neat enough. Having presentaion with czech characters replaced by non size-matching Arial in all slides is even worse than Comis Sans. Actually this idea of using very minimalistic design of slides and just a neat font came to me when I've seen a presentation on Mendel days from some famous guy (I can't really tell now if that was Alec Jeffreys or I'm mixing it up with other speaker) who had a presentation from Mac. No background at all, just very nice font, decent colors (2) and precise letter-spacing. The niciest presentation ever. Jobs surely know how to go with fonts.
For printed text I came to love Georgia (Garamond is also fine, but has a problematic font size or how that parameter is called). Only thing I really hate about it is that it's one of few fonts that have non-lining numerals. Looks pretty odd in your tables. There may be possibly other fonts that look like Georgia, but has normal numerals, but again, problem is it's not a standard font, and that causes troubles when you bring documents somewhere else.