Back in the olden times, parents dreaded the day when their children left home, leaving them to putter around in a lonely and quiet empty nest. But these days, parents have a vastly different outlook: excited to have a spare bedroom, moms and dads can often be found going up to their children and asking, "Are you 18 yet?" After all, a child's old bedroom allots for a plethora of opportunities.

You may take the conservative route, and leave the room just as it is, figuring your child can resume their old ways over the summer and holiday breaks. You may take the business route, and turn the room into an office, somewhere you can work in quiet. You may take the typical route, and turn the room into a nice guest room, complete with a flower-patterned bedspread and brand new guest towels. Or, you may take the creative route and do something entirely different:

Put in a Home Gym: We all intend to work out, intending to go to the gym every morning or on the way home from work. But, life often gets in the way and we put off exercising. One way to avoid putting off this putting off is to stop trying to go to the gym, and bring the gym to you. Fill your spare room with weights, a treadmill, an elliptical machine or an exercise bike (don't forget a television and stereo system). Make working out easy and fun: exercise at home, watch television as you sweat, and, when your kids come over, charge them a membership fee.

Put in a Playroom for Your Grandkids: If you have grandkids, or some on the way, you can help assure they will visit by putting in a playroom. A room that is fairly easy to decorate, with brightly colored walls, a few dressers, toys, games, and stuffed animals, a playroom is a great way to keep your grandkids, and their mess, in one area of your house. This not only makes it easier for you to baby sit, but it also appeases the children. And, of course, it is the first step in making sure you are winning the title of favorite grandparent.

Put in a Relaxation Room: What better way to reward yourself for raising your children than turning their old room into one that perpetuates relaxation. A relaxation room is a chance for you to go somewhere when you need to relieve stress. A room filled with subtle colors, soft chairs, large pillows, candles, comforting scents, and the sounds of water dripping from an indoor fountain, a relaxation room is a great place to draw, nap, read, or do other relaxing things, such as practice yoga or meditate.

Put in a Hobby Room: For those of you who are collectors, inventors, creators or hoarders, you may find that your life's hobbies are forced to live in basements or attics, places where no one can see them. Well, it's time to dig them out, dust them off, and put them somewhere visible. A spare room gives you this somewhere visible; it is a virtual display case, a place where you can hang up paintings, place train sets, arrange Green Bay Packer memorabilia, or set up ceramic pots.

Put in a Wine Cellar: The older we get, the more important it becomes to drink wine; it has far too many health benefits to ignore. A wine cellar not only allows you to have wine readily available, but it also allows for you to get into wine collecting. Wine cellars are not easy to put in: they involve a series of building steps to assure an area suitable for wine preservation. To begin, you will have to think about wine racks, flooring, lighting, cellar doors, and whether you need an active cooling system. It may involve a lot of work, but in the end you just may find a room you can not help but toast.

After the children have left home, their spare room can be turned into anything. Just be sure you turn it into something, leaving their room exactly the same might encourage them to move back in.