I have a few different small profit centers (VERY small) and one major one, which is web consulting/designing/etc.

I'm worried that the smaller ones are tugging at me much more strongly than my main source of income. Writing, for example, really pulls me, as does building organic garden spaces for people. I might starve if I tried to live off those alone. I'm also starting a blog/site that is centered on having an amazing life (food, art, spirits, travel, etc) and still being "green" - that's such a strong pull that I find myself staring out the window daydreaming about it when I should be programming somebody's web site

I know it's not for everyone, but I love having more than one profit center. It keeps me energized and interested in life. And it's a way to do things now, rather than the perpetual "oh, I'll have time to do that when I retire".