Best way to index large text/varchar fields

["Chris Hoover" <revoohc@xxxxxxxxx>]

In 8.1, what is the best way to index large text/varchar fields for wild card searches?

I am getting good number of queries being submitted for reporting purposes that are doing the following - where <text/varchar field> like '%some phrase%' and ....
Is there a good way to index these fields so that the db engine will use and index?

Thanks,

Chris