SharePoints bails out if more than 10,000 search results.

Toy (but expensive!!!) search engine called FAST Search for SharePoint 2010 bails out if using wildcards and it decided that the query may return more than 10,000 results...
Good article about how to increase the limit.

Free FAST Search for SharePoint training

http://msdn.microsoft.com/en-us/sharepoint/ff960976.aspx