I've been having fun maintaining my side web design and development "business". It keeps things interesting outside of work since I love making cool things and helping smaller businesses with their online presence. I started hosting client sites earlier this year while I previously used shared plans for side projects and I think it's one of the better decisions I've made. The control of having a VPS that just works without messing with clunky shared plans is liberating.
While it's a bit of a battle with my free time, I try to keep my projects outside of my 9-5 realistic. I'll likely turn down things that tread into enterprise-level or lots of unknowns since that's what I do full time. This makes sense and I haven't run into anything that has been too big yet.
That said, I'm always looking for new opportunities to design or host client sites. If you like some of my portfolio items and want to work with me, send me a line. I'm not a dirt cheap developer but I will get the job done quickly and well. I've been doing this my whole life!