We just launched a new service for sharing short Bible URLs on Twitter and other places where every character counts. The new site is called ref.ly.
It will generate shortened URLs, but since it uses normal Bible references, you can create them yourself without having to visit the site every time. And the good news is that it recognizes every conceivable Bible referencing scheme, so you can share Matthew 16:18 as http://ref.ly/Mt16.18, http://ref.ly/Mat16.18, http://ref.ly/Matt16.18, or http://ref.ly/Matthew16.18. The benefit to this is that you can just create your own URLs without having to remember which referencing scheme we support.
You can share a single verse (http://ref.ly/Ro8.28), a range of verses, (http://ref.ly/Jn1.1-18), a chapter (http://ref.ly/Ps23), or a book (http://ref.ly/Jd), and you can even specify a particular version by simply adding @ followed by the version abbreviation (http://ref.ly/1P2.2@ESV).
We hope you find ref.ly useful, and we welcome your feedback.