In the last 6 months his only non-unanimous majority opinions are: Chavez v Martinez and Woodford v Garceau. The former was one of the more important decisions this year which said that the government does not break the 5th ammendment by compelling testimony so long as this testimony is not used against the person. It's a rather complicated decision because there are different majorities for different parts of the decision, but Thomas wrote the most important part and announced the decision.

The links are to findlaw which is a really good reference for all things legal.