I'm using version 8.0.4.0 on a Mac, and recently made my own .otf and .ttf fonts at PaintFont.com. The font can be based on pretty much anything, including handwriting, and covers everything from alpha-numerics, symbols, alphabets from other languages, punctuation, and ligatures. This can be very useful if you want your figures and text to look a little more personalized.
The good news is, when I use something like:
Text[Style["This is the text I want in a different font.", FontFamily->"Example Font"]]
basic alpha-numerics, capitals and lowercase, work just fine, but certain symbols, including ! @ # % ^ * ( ) ~ - = + [ ] { } ; : | < >, Greeks, and so forth, show up simply in Mathematica's default font, even though I have characters for my font that definitely work (I've tested them in Word, etc.).
Just an example, if I type:
Text[\[CapitalSigma]]
I get a capital sigma in default font, even though I definitely have that symbol in my own font.
Is there any reason why Mathematica would accept certain characters from a font and not others? Are these characters "reserved" somehow by Mathematica and are "unformatable"?
Thanks!