Tesla offering $2k (1k discount to buyer / 1 k to the referrer) to existing customers and their friends when referring a new customer.
God I wish I had my tesla already – refer 10 people and the deal gets even better !

From Tesla :

Anyone who orders a new Model S before October 31st using the referral link of a current owner will get $1,000 off the purchase price. In return, the current owner will get a $1,000 discount that can be applied to a new car, service center visit or accessory. Referral discounts are limited to ten and are awarded on a first to purchase basis. New orders must be placed prior to October 31, 2015.

In addition, those who make five referrals will receive an invitation for them and a guest to attend the Gigafactory grand opening party. Those who make ten referrals will get the right to purchase a fully loaded Founder Series Model X, which is not available to the public, for the price of a base-level Model X—roughly a $25,000 saving. The first person to make ten referrals will get a fully loaded Model X for free.