Google’s URL shortener even shortens URLs, previously shortened via other services
Google’s URL shortener Goo.gl was introduced last December as a part of Google toolbar and Feedburner and there wasn’t a direct way to shorten URLs via this service, like the Facebook’s URL shortener fb.me. Goo.gl was then integrated for most of the popular services from Google including Picasa, Blogger, Maps etc. A few days ago, Google opened the URL shortener for everyone, i.e. you can open up Goo.gl on your browser and shorten any URL on the fly. But Goo.gl accepts links previously shortened through other URL shorteners as well which is uncommon among other URL shortening websites. Like if you take a link shortened via bit.ly and insert it into the shortening field of Goo.gl, it still accepts it, unlike other URL shortening services which mark such practices as spamming.