With side projects, the reasons why people have them seem to be as varied as their projects. It can be a fair bit of effort to grow and maintain a side project, so I'm curious...
Why you do it? What makes your side project tick?
The work dried up, partly "naturally", but also partly because I wasn't pursuing new work. I've been in a somewhat dead-state for almost a year, and have recently stumbled on two ideas that I've made my "passion projects". Neither idea has a (directly foreseeable) method of making money, but both ideas are near and dear to me.
I work on these ideas when I'm not too tired in the evening, or can find a stretch of time to concentrate on the weekends. So far it's hit or miss, but I'm progressing. One idea challenges me mentally, and has a near-epic scale result at the end of it's very long yellow-brick-road, it's a vision that in addition to all of my coding effort will take 10-20 years to come to fruition.
The other idea is effectively a CRUD system for a specific market demographic that's not being serviced the way I think it should be.
So far, neither is ticking, but give me time, and they will. :)
Out of interest, was the work that dried up similar to your 9-5 at all? And when you say near and dear, what are the ties that keep them close to you? Feel free to not answer if that's asking for TMI :)
The shorter term idea is related to beer, and I'm a homebrewer, so that keeps it close. The longer term idea is related to a game I enjoy playing.
I won't be so much putting a solid 10-20 years into something, as I will be waiting 10-20 years for information to be distributed and produced using my software. The software itself should take less than a year of part-time development (if the ideas required succeed), and then idle maintenance/improvements over the course of the 10-20 years required to achieve the final result.
If you're more curious than my broad rambling fulfills, email me and I'm happy to provide specifics. I'm not trying to be secretive, other than I'd like to have something to show before I make any sort of "announcements".
2) Allows me to learn technologies that interest me but are not used in my day-job.
2 is interesting - it seems to be that format of learning through use that does it. i.e. The benefits in what you learn from a side project vs. what you learn from a presentation.