The spleen keeps the blood tidy and fresh. This queen of clean serves as the primary blood filter and largest lymph organ. It brings blood into contact with lymphocytes, which happily attack foreign bodies, and cleans worn-out red and white blood cells. "This adorable 6" x 6" plushie is perfect for the lymph enthusiast lurking within us all," Wendy Bryan, founder of I Heart Guts, told TDmonthly. Launch date: May 5, 2009.