Everything that is free and positive must be given. Smile, care, friendship, compassion, love, ... Gratitude!

I gree with you, Nany! Are you Thai? In Thailand people smile everyday and its really nice! I'm back in Europe and notice how people pass eachother without even looking at the other person. Maybe the sun makes people smile :)

About the use of grateful for or grateful to...both is possible!

I paste from http://www.ldoceonline.com/dictionary/grateful: ;

grate‧ful
1 feeling that you want to thank someone because of something kind that they have done, or showing this feeling [≠ ungrateful]
grateful for
I'm so grateful for all your help.
grateful to
I am very grateful to all those who took the trouble to write to me.
grateful (that)
She should be grateful that he was making things easier for her.
extremely/deeply/eternally etc grateful
I am extremely grateful for the assistance your staff have provided.
Our grateful thanks go to all who participated.
She gave me a grateful look.
2 I would be grateful if you could/would ... formal used to make a request:
I would be most grateful if you could send me an invoice in due course.

thanks!

autually,i'm chinese.

Smile is the most beautiful thing in the world. When we give it to others or receive it from others, we can feel the charming smile like sun shine in our heart. Smile is an optimistic attitude in our life. Coming cross difficulties, just smile to them, life is going to be fine. Something lucky knocks, we take it and give a smile back, because we should be grateful for the luck, so we can gain the luck next time. In one word, smile makes lucky.
ok, i have corrected them.

I agree 100%  with you. Smile indicates the positive attitude of people, their way of seeing life and it is nice to get a smile and return it to the other person.

nice words nancy ..but i think there are some mistakes in the preposition like : attitude in ( not to) ,just smile to ( not at ), grateful to ( not for) ....rather than that good and i`ll smile :) :)