I'm a younger monk, but I really related to your question. I don't have an answer, but I have my own perspective of this issue.

One thing I have realized is that I have a drive to be creative. I've generally found this fulfilled outside of work, like writing poetry, drumming, and other pursuits. I spent 10 years as an academic, teaching biology, and doing research - a little creative, but not much, which is why I needed the non-work outlets.

I've now spent 2 years doing a lot of programming - primarily in Perl. I'm hoping to move to working 3/4 time as a programmer. I find that I am really happy coding - that I find it a great creative outlet.

Now to the permanence issue. Maybe this is too philosophical, but my perspective is that nothing is permanent. I'm happy if a database I design, or a script I write, gets used by some folks for a while and does some good in the world. (I too, work for non-profits, primarily) That, and the creative juices that get flowing in the process of making the product is enough for me.