I found this on Pinterest today. It's from a blog called Mrs. Lilien. Check out her original blog post here.
My favorite is probably sling back peep toe. They are versatile and the most comfortable for me, plus I think they look classy and stylish. These would not be appropriate for a business professional or interview outfit (those should always be closed toe) but would definitely work for a business casual day in the office. Here are some of my favorite styles: