<p>Thank you for all of the responses! Lots of things to consider. The wedding is this weekend, so I need to act fast! </p>
<p>I really like the mounted letter idea. That would be good for a plethora of different occasions! And also, the passport cover thing is a good idea too! I know they just got their passports recently because their honeymoon will be abroad, so that would be a fun thing to give them.</p>