I get periodic requests about fonts for Greek, so here’s a summary of fonts that include Unicode polytonic Greek. I’ve not listed sources or platforms (Google or Bing are your friends for that info.)
There may be others, but these include at least the standard fonts on Mac OSX 10.7 and Windows 7 along with other fonts that I am aware of that are free or have been available for free at one time or another. (That is, I’ve not purchased any commercial fonts, and I have legal copies of all of these on my system [which runs both Mac and Win7]; one might have been a review copy?) Not all versions of these fonts may contain polytonic Greek, but the most recent versions do. I’ve included a pdf sample sheet at the end.
If you know of others, let us know in the Comments.
Arial Unicode MS
Cambria (& Cambria Math)
[Galilee Unicode Gk: deprecated!]
Microsoft Sans Serif
New Athena Unicode
Silver Humana 2
Times New Roman
Adobe Text Pro
Here’s a 2-page pdf that provides a brief sample of each of these fonts: lower case alphabet and a few caps and diacritics.
To save you browsing the comments, here are some additional fonts mentioned by readers in the comments.
Greek Font Society fonts:
I also see on their site:
GFS Goschen Cursive (a “cursive”/script font)
GFS Decker (This one I must definitely check out for no other reason than the name! It is an interesting looking font with old uncial style glyphs—event he lower case look like the old uncial shapes.)
(There are type specimins on their website. The ones I’ve listed here are only the 19th–21st C. fonts; they have older fonts also that I’ve not had time to explore or list.)
GNU FreeFont family
Another SIL font (that I don’t particularly like! but each to their own in this department…)