A few years ago we had jumpseating mechanics almost 3-4 times a week. However most of the time it were the same money minded mechanics that did go with the a/c, and the mechanics that would really enjoy the flight had to stay on ground. If you were of the last type, you would do 1 or 2 trips a year.
These times however, very few jumpseats, most of the aog work is done by contracting people.
We have a few loadmasters, I think that is the job that offers you the most jumpseat time without being a pilot yourself.