Thanks, BigH. I have been seeing news reports on how many retired "baby-boomers" are doing worthwhile volunteer work to "give-back" to society. The interviews often stress how the "boomer" comes to see this activity are one of the most rewarding things they have ever done.
It has slowly dawned on me that this is how I view engineering-tips (a worthwhile volunteer activity that has it's own, built-in, intangible rewards).