$4 gas, and what have we learned?

Gas yesterday hit the big 4-0-0 in Indianapolis

Techincally, it's $3.999 (is that little 9/10 of a cent to make you not feel so bad?). Who knew I would ever live to see $4 gas.

The sad thing is, other than being broker and everyone I know whining more, little outward changes seem to be happening. Yes, some stores' sales are down, like Target and Lowe's, but little widespread change in our habits is occuring yet. The highways are still cluttered, but the grocery stores are empty on the way home from work, when people could instead be piggy-backing their errands onto their daily commutes. People are still planning road trips for Memorial Day weekend, and the farmer's market, which features locally produced goods, truly wasn't that busy last weekend.

So the question is, if we're scrimping to make ends meet as the media tends to report, where are we making the changes? And are we honestly doing it in real ways that make a difference? What have we learned? And what real changes will you make?