http://www.chron.com/disp/story.mpl/metropolitan/5040779.html
Sorry if you've already seen this. From the article it says that in order to get some of the heavier polluting cars off the roads in certain Texas counties the state will be offering $3k-$3500 vouchers to retire your pre-1996 vehicle. The vouchers are only good for newer cars that cost less than $25k and your income must be under $61k.
I have a bad feeling that the cars they 'retire' will end up for sale here in Oklahoma, sigh.
Eagle