What's a trendy word for an 'information capsule'. A short snippet of information
Snippet, which you referenced, is already one word for a small piece of information.
A blurb would be one word you might use particularly in reference to self-advertisement of a book, movie, or product.
A tidbit has connotations of gossip or news, or used to describe something that is secret, overheard, or Incidentally acquired.
A nugget (via RegDwigнt) can describe a small lump of anything, including information, often in the form of a proverb or "nugget of wisdom."
You said "trendy" but more formally an abstract is a summary of a text or a scientific article.
A synopsis is a summary of a book or movie plot, or more generally, a condensed summary of a particular topic.
In publishing, sidebar is a term for information placed adjacent to an article in a printed or Web publication, graphically separate but with contextual connection
https://en.wikipedia.org/wiki/Sidebar_(publishing)