There aren't any ways that I can tell you about. :p
It really ticks me off that the dealers basically have a corner on the market of replacement PATS keys. The keys and the labor to program the vehicle to accept them are seriously overpriced.

The key shouldn't be any more than $5 and they shouldn't charge any more than for the 10-15 minutes labor it takes to go through the reprogramming security process. That process isn't even required if you still have two working keys--then it takes less than a minute.