Special thanks for your gift suggestion of donating to charity. What a wonderful gift to give or receive. There is a website that addresses this very issue, it is www.wishlistcomplete.com.
Wedding gift is an art. You should know what is close to their heart. Offer such appliances which will be useful in the kitchen Ensure that it is not duplicated.
Most of them prefer money because an auspicious beggining with money inhand goes a long way. Its the belief money multiplies and the foundation is strong. So cash or savings in any form is a nice gift.
For people who cant spend much but would like to add charm to either, a slam book with milestones and knowing each other is a wonderful gift. First moments, likes and dislikes are so clearly mentioned that can aid either of them to understand the other. It also gives time for togetherness and understanding when involved in such an activity. Its not COST its bringing two people together and oiling their machinery called life.