you like best or find most helpful is usually 'awarded' points. It's how people are thanked for their time and effort.
2.6 Askers must close "help" questions. Close questions by selecting the answer deemed most helpful (and awarding it points, unless the question was posed as "not-for-points"). Askers who do not close their questions within an appropriate period of time are not permitted to ask further questions.
Note that when no answer is deemed helpful, it is possible to close a question without selecting a most helpful answer.)
http://www.proz.com/siterules/kudoz_asking/2.6#2.6