20-35 min of cardio at gym. I lifted for about a year, had a wrist injury so I started doing the recumbent bike. Hold 130+ heart rate for 20-25min. I wish I had done this when I started going to the gym, this combined with audiobooks took the "chore" out of cardio.

Also treating every bit of time like it is; a precious non-renewable resource, has helped more than it's hurt :).