Instapundit points to an article about sinus washes as a treatment for sinus problems. I've been using NeilMed's product for several years, and I do think that they help. But I would say that the Breathe Right strips that I have discussed here have been more useful. Of course, it's not a choice; you can use both.
One downside to sinus washes--you really need to clean the sink carefully afterwards to maintain domestic peace. There's no question that the saline wash removes stuff from your sinuses--the evidence is unmistakable.