What happens when I grow to more than 100,000 documents?

You always have the option of upgrading your Mini to a 100,000, 200,000 or 300,000 document version. The upgrade process to a higher document count license, up to 300,000 documents, only requires purchase of a higher document count license. The cost of the new license is the cost difference between the new license cost and the license cost of your current document size. For example, from 50K to 100K document count, the cost would be $3990-$2990=$1000. The cost beyond that is $3000 per 100K document count increase. You can add additional capacity to your existing Mini by going to your customer profile on the Google support site and clicking the "Upgrade" link.

https://support.google.com/enterprise/login?dest=%2Fenterprise%2Fprofile

You might consider purchasing an additional Mini if you want to separately index another set of documents. For example, if you are providing search on your intranet and also want to provide search on your public website. You can purchase an additional Mini on the Google Store:

http://www.googlestore.com/appliance/GO0123.asp

Finally, should you outgrow the Google Mini; you should consider the Google Search Appliance. The Google Search Appliance supports from 500,000 documents up to billions of documents. The Google Search Appliance includes many advanced features, such as indexing and searching content management systems, databases, dynamic result clustering, query stemming, and much more. Find out more here:

http://services.google.com/appliance/request_info/site