Thumb Score: +16 Amazon [amazon.com] has 10-lb Yes4All Fitness Slam Medicine Ball for $16.67. Shipping is free with Prime or on $35+ orders. Price $17.32 lower (51% savings) than the list price of $33.99 $12.56 lower (43% savings) than the previous price of $29.23 *Previous Frontpage Deal at $17 with 57 Deal Score and 11…