Far easier for than just a simple Top 5 or Top 10. Many games I love.
Here are mine, not in a specific order:
01. Duke Nukem 3D, PC
02. Death Rally, PC
03. Saya No Uta, PC
04. Ghost Trick, NDS
05. Portal 2, PC
06. Heroes of Might and Magic 3, PC
07. Noitu Love 2: Devolution, PC
08...