So here's the deal - Like my mom, I go snooping around in junk stores on a fairly regular basis. Best HP deal I ever found in one was a 12C for about two bucks.
My dad on the other hand, can't stand those stores, so he seldom enters one. So he called me over the Christmas break, as he was standing in a store waiting for my mom (mom likes to shop), and asked if he should buy this calculator for $.98. It didn't have any batteries, so he couldn't tell if it worked. It was a 15C, so of course I told him to grab it. So he walks down the aisle a few steps, and lo and behold, there was another one! Two 15Cs for a buck a piece! But don't answer yet - Turns out, it was half price day, so he got both of them for a buck. :^) (Yeah, I feel kind of guilty for hoarding.)
He also found a 48GX once for $10 at a different store, also while waiting on my mom.
I hope I can grow up to be like my dad some day ;^)