If you want to make a clean install of the new OS X Mavericks or even the older versions of Mac OS X, than I strongly suggest you to create a bootable OS X key or a drive.
Some websites overlay their photos and images with another blank image. But there's an easy way to download those pictures if you are using Google Chrome browser.
If you know how to sing or hum a song, but don't know the title or the artist performing it, you can use a midomi website which will help you find the the song.