Thank you note

I just got in the mail today a thank you card from a friend that got married recently. It didn''t say anything major, just thank you for the gift and being part of my wedding. may we share in more simchos together. Mind you, I did not give her a personal gift; I just chipped in the money like everyone else that was invited. But I thought it was so nice. I have been to many many weddings and so she was the only one that I received a thank you card from. I wasnt expecting from anyone, but now that I got this one, and it wasnt even from such a close friend, I see it makes so much of a difference and it's a really nice thing to do. Doesnt take alot of time and effort but can really make someones day!
Just a thought.