Used to be probably the largest and most popular site hosting links for the edonkey network. Its owner, SimonMoon got arrested, and his hardware taken by the authorities, for breaking copyrights. This was of course a mistake, because he did not host any of these files, they were hosted BY the users. He was also forced not to use the domain sharereactor.com , so the site is history now.
THE ONLY sharereactor site had sharereactor.com domain name. Any other domain names are just owned by people who steal on other sites popularity for their own concern.
If you want to see how the story develops, be sure to check out SimonMoon's recent website, www.respectp2p.org