Floating Flower Tip - Most flowers float pretty well on their own until they start to pool with water and slowly sink. For a longer lasting centerpiece, use bubble wrap to make little skirts for your flowers.
Cutest office gift ever: Hearts & hyacinths. "forced" bulbs for the holidays. Amaryllis with white hyacinth & red tulips in a clear container with just stones and water, no dirt. Then tie a beautiful ribbon around it.