Any way to save money on Cingular(AT&T) wireless??

I'm currently using the 450 minutes plan, 39.99.
but, I have rollover minutes of about 1200 minutes.
And I don't think I'm gonna overuse minutes.
Is there any way that I could get a benefit from the rollover minutes? It is useless for me.
Don't say 'Talk more'. That's what I heard from an AT&T retail store customer service today.