Been receiving lots of CDs for online service in the mail? Are you tossing them out in the garbage? Not so fast. Today, you'll learn how CDs blowing in the breeze save plants and trees. Here's how: From deep within the Carey Brothers' vault of online recycling, we bring digital double-duty. Here's something useful you can do with all those free CDs. Drill a hole in the edge of each disc and thread thin wire, twine or dental floss through the hole. Then hang them from your fruit trees; the silvery, flashy surface will scare birds away. You can protect low- lying fruit plants and vegetable gardens, too, by hanging these digital scarecrows on coat hangers bent into hooks, and sticking them in the ground. Got pesky birds or small critters that nibble? The answer, my friend, is blowing in the wind. And that's the On The House Tip for today.