We do what we call 7 Ups. You do them with a partner (or more) Person #1 runs the length of the gym and back. (we run the width of the basketball court) Then person #2 runs down and back. Then #1 does 3, then #2 does #3. Then 5 then 7 then 5 then 3 then 1. So you are recovering while they are running.
I like running the stairs we usually do 3 minute rounds on the stairs mixed in with the other conditioning. They really work the legs and it gets your heart rate up, you should try them.