I try to exercise at least 30 min a day.

We (my wife and myself) use an Indoor Rowing machine made by Concept2. I like to row for about 10km a day (approx 39min 30sec duration).
Or for 30min duration which I am able to do about 7.7kms. On the rare occasion I will do a half marathon (21097mts) and that takes about 1hr 24min.
Concept2 have an online log book, which I enter my times. They also have online challenges throughout the year.
At the moment (in March) there is a challenge to row either 5km or 10km for 25 days or more in March.
Last year I did the easier one and completed 5km for the 31days.
This year I have undertaken the harder challenge of 10kms every day. So far so good (18th March 2010).
Yipee I did it, see the certificate here. Now going for 31 days straight.

Here is an action shot of me about to start a 10km row. I am totally saturated when I finish.

My wife also rows as well, but I cannot keep up with her. She often rows a half marathon (21097mts). Her average for this rowing year is about 12km/day.
Mine is about 5km/day. She has clocked up almost 5million meters, whereas I have done just over 2million meters.
We were interviewed recently by ABC radio on our rowing and on our motivation. You can read about it and listen to the interview here.

I have been rowing for a bit over a year now and have shed about 22kg since starting. My wife has lost over 40kg. A GREAT way to keep in shape.

Here is a table of my best times for the different distances/times.

2000 7:22.8 1:50.7 24/July/2009
5000 18:47.2 1:52.7 5/April/2009
6000 22:33.3 1:52.7 26/May/2009
7824 30:00.0 1:55.0 2/Dec/2009
10000 38:19.2 1:54.9 2/Jan/2010
15433 60:00.0 1:56.6 16/May/2010
21097 1:22:58.1 1:57.9 7/May/2010

As you can see, I am concentrating on my long distance endurance.
I love doing the 10k distance, but also love the mind challenge of the 1 hour and half Marathon. One day I will try the Full Marathon.