Hidden Jewelry Holder - This is an awesome DIY project. All you need is a couple nails, some hinges a little bit of altering and a place to hang a pretty picture. I think it's a good idea, and a convenient way to hide your valuables.
"Stones and Rocks DIY Wedding guest book". Guests write messages to bride and groom on rocks with Sharpie instead of signing traditional guest book. This would be cool to put in giant glass vases on either side of the fireplace once the wedding was over.