A nano-lollipop? This is a tiny glass ball on a tiny stick made of polymer, a partially-completed nano-sized chemical sensor made by then-grad-student Matthew Chen. It’s on its way to becoming a nano-torch, which can detect minute concentrations of chemicals due to its ability to focus light.
This whole thing’s tiny (pretty much everything I post is tiny, but this is tinier than most). The little glass ball on top is about 1/25,000th as wide as a single peppercorn.