Nice Referral System

I was browsing the Heat Online website and noticed they have an affiliate program. I read through their program and it was pretty cool.

Both the referrer and the referral will benefit from this program, which is pretty nice because usually its only the referrer that gains anything from an affiliate program.

How it Works
The person that is referred will receive some free cars that have a limited duration from one week to three days. This way they get to have some fun with different cars and different game modes right away and don't need to spend all their time with just the starter car. The cars they get are a Kawana, C-Racer 4x4, and a TA Rookie.

The person that refers people will receive ten double experiences and ten double RP items after the person they refer becomes level 15. So this encourages them to play with their friends and help them level up by showing them the ropes of the game. This also discourages them from signing up multiple accounts, because it is basically a waste of time to level up a new character to level 15.