I just did an experiement: The site Bit.ly makes short urls. For example, the string http://bit.ly/mcSRz leads straight back here.
You can paste the stort string in a twitter post. Twitter will make the shortened URL hot.
Twitter makes any string beginning with www. hot. If you replace the "http://" with "www."
The new link seems to work and you save three characters ... which is important in a world limited to 140 characters.
PS: I am not with bit.ly and can not guarantee that this hack will work forever. (Back to twitter (twitter links).