Your smite attacks are much more powerful than normal.
Prerequisites: Cha 25, smite ability (from class feature or domain granted power).
Benefit: Whenever you make a successful smite attack, add twice the appropriate level to damage (rather than just your level).
Special: You may select this feat multiple times. Its effects stack. (Remember that two doublings equals a tripling, and so forth.)
Source: Dungeon Master’s Guide (version 3.5), page 209.