Weird, I've just in the last few days been playing with SMS to web stuff. I was just today wondering about making a more general system but since in the UK it costs to send messages (i understand the cost is on the receiver in the US) I couldn't think how to make it work.

The exception would seem to be for things that have the potential to make a return, if you're in the UK my amazon price checker will send you an amazon.co.uk price when you text PRICE and the product name to 07786200690.