'Not many' isn't the same as 'none' though. I wish maybe when I was back in my early 20's, I hadn't been as much of a drinker, or gambler. I was never really in danger of being an alcoholic, and I never had to attend Gambler's Annonymous meetings, but that was primarily due to the fact that I was a young single guy living in the barracks. I didn't have much in the way of family to support, or anything else to spend money on, other than beer and gambling. So...no one was hurt, and I broke both bad habits as I aged, but let me tell you...there are times older, more mature me could sure have found a use for an extra $25K.
Another regret was hammered home to me just this evening. One of our Christmas gifts to ourselves was a new digital camera. That meant it was time to make sure the other camera was well and truly emptied out, including the little used internal memory, which yielded this long forgotten about jem, from when my oldest one was the only one.
Watching this made it a little dusty in the room for both my wife and I. We didn't record nearly enough video as my kids were growing up...of either of them. We took a fair amount of pictures...but precious little live footage.
That is a pretty major regret...and I'm not sure what format will exist in 20 years, but when we have grandkids, I'm gonna have hours of footage of them.