Instagram has added the option to share others' posts as Stories. Users can now tap on the share button below every post and will see an option to add it to their story. The image can be customized before posting.
The ability to share other people's posts have been often requested by some users. While a Twitter retweet-style feature could have been implemented, I'm glad Instagram went down this route and instead letting people post it as a story as this way it doesn't add to the already increasing amount of distracting unintentional posts polluting the users' timelines (which are still not chronological, by the way).
The share to story feature has started rolling out and will already be available for some accounts. For others, expect to see it in the coming days.