FMIL brought up a good favor idea

My FMIL was telling us about a wedding she went to where the favor a picture frame--the couple put the table numbers in them. She said it would've been really cute if they sent a thank you card with a picture just the right size to fit into the frame. How cute is that? I'm doing the watercolor thank-yous, but figured I'd pass on the idea.

BTW: the couple never even sent her a thank you, so she doesn't know if they ended up doing this!