Cats love to climb and scratch on sisal posts.  Not only do they help groom their nails, but they also give them a chance to stretch after a long nap!  My cats always loved their sisal posts.  I have several that are attached to cat trees and have spots for napping, climbing, and playing.  At the Cat Shows there is usually a sisal post attached to each judging table.  The cats are always attracted to the post and while they are distracted and climbing, the judge has a good opportunity to examine their body and coat.  This pretty cat was taking full advantage of some play time!