I've had lots of ideas like that, things I'd like to do which I never get around to. The one I did go through with and still keep working on it on and off is th

I've had lots of ideas like that, things I'd like to do which I never get around to. The one I did go through with and still keep working on it on and off is the one that had a connection to my job. I worked on a very concurrent system and thought maybe STM would be a nice fit for it. I found the concept of STMs very interesting. And I noticed that, although there were many implementations for .NET, all were one-off projects, not maintained, and in my opinion not very nice to use. So I ended up writing one myself. I guess that sweet spot for me was having a problem that I dealt with on a daily basis, which gave me the drive and a clear picture of what I'm trying to achieve, and the fact that it was a fun challenge to implement and a learning experience related to a concept that intrigued me. The other ideas I had would mostly have just that second part - they're fun, challenging, but not really solving something I deal with too often. So, I don't have much experience, I don't have many side projects, but for what it's worth, my advice is to try to find something in your day-to-day which bugs you, and for which you have some interesting idea that you'd like to experiment with.