A few days ago I had to upgrade my hosting plan. I had a $10 hosting plan, so I was enjoying a very good ROI until my sites started to exceed the CPU usage limits. The problem was caused by Googlebot which was constantly crawling my site at 4 pages per second, in other words about 350,000 pages per day. So I moved it to a private server. That site has only 5,000 page views a day, so compared to googlebot activity it's nothing. That's why I was hosting it at shared host and it also was a challenge to optimize the site's engine so that it would process the page as fast as possible. It was processing database queries between 0.0004 ... 0.002 seconds.
My options were either to make the queries even faster, limit the crawl rate to 2 requests per second or upgrade the hosting.
I wonder what would you have done?