Had been using the j.mp URL shortner bookmarklet for long for posting to Twitter. Recently discovered that the bookmarklet was no longer doing so & was instead creating shortened bit.ly URLs, both URL shortening services being run by the same enterprise. From now onwards, in order to create a j.mp URL, one has to sign in into the service & only then would it be possible to do so - *hate* signing in anywhere & avoid it as far as possible.
Turns out, as of the time of posting, bit.ly & j.mp URLs are inter-changeable, i.e, if you had created a shortened bit.ly URL, then it is possible to shave off 2 more characters by simply replacing the bit.ly by j.mp without any change in result. Critical, if one posts on twitter, where character real-estate is a premium. However, with growing number of URLs being shortened with their service, it may be just happen that they decide to turn j.mp & bit.ly URLs unique. Until that time, no signing-in required to create a shortened j.mp URL.
Example:
Original shortened bit.ly URL: http://bit.ly/ujkp5
a j.mp URL created by replacing the bit.ly: http://j.mp/ujkp5
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Was looking up something, when I came across this site still hosted on Geocities. Ran a Google search query & found out, as the URLs above indicated, around 60,000+ sites continue to remain hosted on Geocities. This does not count their service in Japan, which they continue to run. However, considering the fact that Yahoo! was supposed to have shutdown Geocities.com, it was indeed surprising to find these pages still there. Will try searching around for an answer. Some kind soul could cut short my work & save me some time by posting the answer, in the comments below, though.
Godspeed