Long URL addresses are annoying and difficult to manage. Is.gd is a solution for anyone having to work with them- the website will convert any URL into a shortened address using the is.gd domain. For example, if you want to send a web link in a text message, a long URL address is inconvenient and more costly. By shortening it with is.gd (URLs generated through this site will never be longer than eighteen characters, including the “http://”) users simply click the .gd link and are immediately directed to the intended site.
Why it might be a killer
Long URL addresses are a hassle, but I think that some of the most interesting aspects of is.gd have nothing to do with the length of an link. The ability to hide your email address from spammers but still have it be “clickable” is great, as is the ability to post an entry about your competitor or a website you dislike, but without having it add to their search engine rankings.