Just discovered two new toddler-entertaining ideas for while I'm working. (Experienced mommies probably already know these...)
1) put a bunch of toys in a big cardboard box and let her figure out getting them out and rearranging them
2) say "where's the ___" and let her go find whatever - eg. a shoe
Oh, here's another I'm a little ashamed of: I play "fetch" like I would with the dog. I throw a stuffed toy across the room for her to run and bring back to me! Or a small, hard toy I throw to the couch opposite the loveseat where I'm sitting.

Shame on me, but I'm too busy to give her all my attention. At least this game keeps her occupied and gets her some valuable cardio exercise, right?!
Anyone else have a shameful way of entertaining kids while you work?