Try the Grossan Sinupulse Elite and put Breathease XL in the water. I have the world's worst allergies and have since I was a little kid. It is like a waterpick for the nose and works great at getting out all the mucus and helps to calm the inflammation. I use it once in the morning and at night before bed.
Also, for those that use a CPAP humidifier, just turn up the humidity a little and it helps to act as a sinus rinse while you sleep somewhat as well.