My own one Search Cydia for "MAC BACKGROUNDS" - it's a springboard theme I made with 17 different backgrounds that randomly change every 8 seconds. Also has the dock seen in my screen shot. "MAC BACKGROUNDS LITE" is slimmed down - 8 or 9 backgrounds and no dock

I also have another hosted on Cydia called MAC WALLPAPERS, which is a wallpaper file that downloads into your SETTINGS>WALLPAPER>WALLPAPER menu with another bunch of images to use on your lockscreen or springboard (if you apply USER WALLPAPER in Winterboard)