Force sensitive resistors

I’ve been shopping around for force sensitive resistors. Basically I’m building a beverage (beer) coaster that has a RGB LED in the base of it. As you drink your beverage (beer) the LED should fade from green (everything is good) to red (I need more beer). I understand that Arduino is overkill (not to mention cumbersome) for this project, so I’ve purchased a few PICAXE’s to get the job done.

Now, all of the commercially available FSR’s I’ve seen run 5 bucks or better. I’ve seen the DIY examples of FSR’s using conductive foam that IC’s ship with, but would like the neat, tiny commercial versions. Anyone know where I can get some for cheaper? And why the heck are they so expensive in the first place?

Does anyone have a better (cheaper) idea for accomplishing the same task without a FSR?

Also, this is my first post here, and I must say that this is one of the best forums I’ve ever participated in. Everyone here is so nice and helpful!

Thanks in advance,
Aneal K.

cheap way out

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=370304820805&rvr_id=&crlp=1_263602_263622&UA=W2F%3F&GUID=0fc8effb1250a0437a605a50fffe4be6&itemid=370304820805&ff4=263602_263622

haha! That’s exactly what I’m talking about! How can these folks build an entire stainless steel scale (with buttons, lcds and whatnot) for that price? Sure, they’re buying in bulk, but wtf?