What is the ruling on receiving financial compensation (one dollar per 1000 people) for shortening links to files uploaded on sites like RapidShare, such that users are directed straight to the original file link?

There is no harm in earning money from "link shortening" on websites that offer financial compensation to those who shorten links through them, provided that registration is free. This earning is a wage for a permissible service. However, certain conditions must be met: the links must lead to useful or permissible topics, free from forbidden content; one must not participate in websites that publish prohibited advertisements (pornography, alcohol, gambling); one must avoid websites that mislead the user by making it difficult to reach the desired page; and one should seek out trustworthy websites and avoid suspicious ones.