boxes are great.

i love boxes, i love putting things in boxes, or cute empty boxes that make me look organized when really i am not. these are some of my favorite 'wedding boxes' via the new issue of the bible (aka Martha Stewart Weddings).
i love these preppy boxes.
AND they can be DIY'd. directions from martha here -

super chic cake box - also from martha

i'm pretty sure i could blow our whole budget on cute boxes for cake, cute boxes for favors and cute boxes to mail our invites and enjoy every minute of it.