Frito-Lay has another promo this year. $2.50 shipping and handling and you get a "free" Sidekick. Last year they did this and they were going on eBay for $20 each.
The promo packs also have coupons that can be used on figures and starter packs. I posted info about it here:
I'm sure with manufacturer coupons you can combine with a price match and make a hell of a deal.