Uniqlo's bargain sales are infamous for massive queues. In order to generate even more customers for the 2010 sale Uniqlo went viral. Customers who tweeted or wall posted about the upcoming sale joined a virtual line. One out of every 26 customers in this line received a 1000 yen Uniqlo gift certificate,
You can find out more about Uniqlo here: http://www.uniqlo.com/jp/