Had a quick look but couldn't find a post regarding this very special offer:

"Get our SilverLine Collection in this amazing Group Buy!!!
Now you have a rare opportunity to get our complete SilverLine Collection for an incredibly low price: buying only one of the SilverLine effects gives you a chance to get all the rest for free!"

There's allready 556 participants (including me) which means
for the price of one plugin you can choose three (3!) other effects from the Silverline collection. If it reaches 750 it will be 4 plugins for the cost of one. Quite a bargain

http://www.d16.pl/groupbuy