Does anyone know how to exchange air mileage rewards/points between different programs? For instance, I have about 5000 United mileage points set to expire on 5/31/13. Instead of using those points to buy magazine subscriptions I came across a site called points.com where it would allow me to exchange those points and transfer it into my Hawaiian miles program but it won't be at a value of 1:1. They will convert it into about 2000 points into my Hawaiian miles program thus keeping 3000 points as an exchange rate. Are there better exchange rate programs out there that you know about.