Found this site regarding fuel economy. Robust, informative and understandable. Its not the 1-10 ways to save gas sites but it gets into more detail. I've spend a couple hours here.
http://www.fueleconomytips.com/

Here's an article on why we use up more gas in the winter. A few I didn't think about.
http://fueleconomytips.com/content/view/66/2/

Edit: Oh, didn't put down my question. Anyone heard of indexing plugs? This site talked about then and using another approach. Is that effective? Does it lower the life of the plugs?

Indexing started with big horsepower blocks, NHRA, etc. I knew some in the turbo Dodge crowd that did it. It was explained that this was done to make sure all cylinders are/were getting the proper fuel/air mixture. Many say it wasn't worth the time and effort unless you were really pushing the upper limits. Never heard of indexing plugs having much affect on MPG though. Not sure if it shortens the life of the plug either.

Here's a good write up if anyone is interested in indexing plugs. I just might try it one of these days that I'm bored.

Plug indexing

By the way he goes into a good why it works and why to avoid the Bosch +4 plugs.