Exercises for people with really bad knees

My friend used to run but did something with her knee and is waiting on surgury. Any suggestions for activities/exercises she can do that doesn't engage her knee at all? She was told she shouldn't even swim - her knee is that bad. Getting up and down off the floor too many times would be hard for her too.

So far I have:
The Bike you use with your hands.

Barbell Row
Holding bar or weights in front of thighs, bend knees and tilt torso forward to about 45 degrees, abs in tight. Take the weight out, following line of thighs, then squeeze the back to draw weight in towards belly button. Avoid this move if you have back problems.

Overhead Press
Sit or stand holding weights in hands, elbows bent and weights next to shoulders. Straighten elbows and push weights overhead, palms facing each other and slightly in front of head. Lower arms and repeat.

Front Raises
Stand with feet hip-width apart, abs in and torso upright with medium weights resting in front of thighs (palms face the thighs). Lift arms to shoulder level, elbows slightly bent and palms facing the floor. Lower and repeat

Concentration Curls
Kneel or sit in a chair and prop right arm on the inside of right leg, weight in hand and palm facing out. Contract the bicep to pull weight towards the shoulder (without touching the shoulder). Lower and repeat.

Kickbacks
Bend torso forward until you're at 45 degrees or parallel to the floor, elbows bent and next to ribcage. Contract triceps to straighten elbows, bringing weight up slightly above hips. Keep the abs tight and raise torso if this hurts your lower back or hamstrings.

Antyhing else?

Thanks!
Charmaine