To truly get away from it all, spend a night or two at Qasr al Sarab. The resort lies on the edge of the Empty Quarter that stretches deep past the Saudi Arabian border with the UAE in endless sand dunes.
The resort is fairly self-contained along an arc of oasis. Activities range from camel riding and walks in the dunes to fine dining and spa treatments.
Be prepared for a couple hours' drive from the City of Abu Dhabi, but the spectacular views and quiet resort atmosphere are worth every second.