Christmas, Easter, winter wonderland, spring fling and even Independence Day are classic themes for centerpieces. The nice thing about using these established holiday or seasonal ideas is that it's easy to get inspired, and the elements to carry them out successfully are as close as your local craft store. If you're on a budget or want something that's easy to put together, stick with candles and fresh flowers that correspond to your theme. They're a classic that never gets old. Seasonally wrapped boxes exploding with fresh flowers are great, too.