Vanessa brings up some good points over at the Webmaster Central blog:
If my site is down for maintenance, how can I tell Googlebot to come back later rather than to index the “down for maintenance” page?
You should configure your server to return a status of 503 (network unavailable) rather than 200 (successful). That lets Googlebot know to try the pages again later.What should I do if Googlebot is crawling my site too much?
You can contact us — we’ll work with you to make sure we don’t overwhelm your server’s bandwidth. We’re experimenting with a feature in our webmaster tools for you to provide input on your crawl rate, and have gotten great feedback so far, so we hope to offer it to everyone soon.
There is plenty more she brings up in this article, those are just a few. It’s worth the time to read it, you just might learn something.
