The exclamation point is not trademarkable!
Tim Berners-Lee apologies for forward slashes // in URLs. It didn't have to be this way.
Nearly a month ago now, Steve posted at Glossographia on a typology of quotation marks.
And finally, thanks to a question from theengineer, if you'd like to find out what font a particular piece of punctuation (or other printed character) is in, try What the Font, from My Fonts.