The asterisk. We all use it. Most of us use it to pretty-up a blog post or as an alternate bullet point. But, as with all glyphs, there's more to it than just that. The asterisk was first used in European typography as a special symbol to mark birth dates, and it's first use is traced back 5,000 years to Sumerian pictographs. Today, it's mostly used in footnotes.
When you're designing something that involves an asterisk, keep in mind that different typefaces have different asterisks. See image above for proof. Use these variations to your advantage; you'll be able to find one that's just right for the job.
Wikipedia has a thorough article on asterisks if you're interested (or just super nerdy).
If you love asterisks, then you might like an entire typeface made entirely of asterisks. I was lucky enough to be a part of the release of Font Aid IV: Aster Affects in 2013. Sales of this typeface go to support relief efforts for Hurricane Sandy. Thanks to the Society of Typographic Aficionados for compiling the typeface.