I have two cats. One likes to make herself comfortable on my lap by way of "kneeding". Since she's not declawed, this can get pretty distracting, but I don't really have the heart to stop her since she's old and probably not gonna be alive much longer.

My other cat is much younger, and when he wants attention he's not afraid to climb up and get in my face. "WANT PETZ NAO." I'm not quite so reluctant to shoo him away. XD

It's rare that either actually walks on my keyboard, but it has been known to happen...