A great gift is to have the wedding invitation preserved. The simplest way is to frame it; alternatively, there are lots of artists who do everything from putting it on the top of a stained glass box to etching it on a platter. Do some internet searching on wedding invitation keepsake.

The reason is that your friend probably put a lot of thought into the invitation, and it tells a story that is meaningful to the people getting married. Rather than putting it in a drawer, it is a wonderful thing to be able to display the invitation - one of the few tangible things left after the wedding - so the newlyweds can enjoy it every day. And it will connect them to the joyous emotions of their celebration.