Tweetbot bookmarklet. I'm sure other people have better, more robust ones, but this bookmarklet works for me.

bookmarklet.js

javascript:(function()%7Bwindow.open(location.href.replace(%2Fhttps%3A%5C%2F%5C%2F(mobile.)%3Ftwitter.com%5C%2F%2F%2C%20%22tweetbot%3A%2F%2F%22).replace(%22statuses%22%2C%20%22status%22)%2C%20%22_self%22)%7D)()

src.js

// Simple and probably error-prone
window.open(location.href.replace(/https:\/\/(mobile.)?twitter.com\//, "tweetbot://").replace("statuses", "status"), "_self");