Being a software engineer I spend most of my time in front of my computer. There was a time when I used to go for jogging in a park nearby. But now its all work and only work. I always used to tell myself that I am going to start jogging by the end of this month, but as usual it never happened. So finally I dropped the idea of going to park and started doing few minutes workout in my office itself and in no time I started feeling really satisfied with my efforts (15 min workout is better then 30 min of thinking about going to park ;-)).
This is what I do on a normal day:
I start with 5 minutes of warm-ups and stretching exercises (going down to the lower floor and coming back is a good way to warm-up ).
After warm-up I do 3 sets of 15 squats, with 1 foot gap between both the feet.
Then I use my chair(without wheels) and do some press ups.
Again I do 3 sets of 20 squats, but this time with wider gap between both the feet.
And finally I do some streching by touching my finger toes (shoe tips actually) with my fingers by bending to the floor(without bending the knees).
After that I take one last round of that lower floor to warm down my body.
All this takes less then 15 minutes of time. And my whole body feels much relaxed, specially my back and legs. Just remember one thing, don't do this workout (or any workout for that matter) just before or after lunch time.