I've experimented with part-time jobs while self employed. The main benefit to me was that it helped give me a regular routine that otherwise takes a lot of discipline to have if you're working from home.
The web maintenance part of your home business could be expanded rather easily. Are you on freelancing websites like oDesk, Freelancer, Guru? They'll take a percentage of what you make per hour and you're competing with people in parts of the world that think $20/hour is a lot of money, but you can find clients and build a reputation.
Given the above, I would suggest you take some time off to work on growing your home business. For the first couple weeks focus as much time as possible on business development, and set a goal for yourself like "line up $X/week in revenue." If you fail to meet the goal, it might be wise to find a 2 day/week part-time job doing something totally unrelated to computers that you still enjoy. It will give you a little bit of income certainty, a way to get outside and work with people, and might improve your time management on the other days of the week.