I’ve somewhat accidentally produced a bit of a thread here on obstacles to starting, the counterpoint about a relationship boost, and then that generated a note of caution, about family and relationships.  These generated some good comments, too; they really added to the discussion (below).

Then, just when I thought we were through with that for a while, Sara and ‘Chelle at Palo Alto Software pointed me to this note in a Freakonomics interview of Digg CEO Jay Adelson: 

You hear entrepreneurs say “quit your day job” all the time … but we didn’t! I continued at Equinix and Kevin Rose worked at G4 when Digg was founded. The key is getting a business plan together in your spare time, and if it’s a Web-based idea, try to create (or have someone create) a prototype.

It helps if your business can take advantage of the low costs of starting companies now. For example, when Kevin started Digg, he only needed a few thousand dollars of his own money to get things up and running, relying heavily on open source tools and the low costs of renting servers, bandwidth, etc. When you’re ready to take it to the next step — which usually means that somehow you’ve proven that the business has merit either by profits or adoption — investors will be easy to find.

That’s certainly a good addition to this thread, pointing out that there are so many variations on this theme. Keep the day job, work extra, validate, and follow that path. If, that is, it’s an option available to you; Jay’s case is special, he already had a track record by then, which makes investment way easier to get for him than for somebody on his or her first time out. Still, he points to another good option.

He comments on the significance of "taking the plunge," which relates to this same thread:

Entrepreneurs are a distinct breed, so I would also recommend doing a lot of research on the qualities of entrepreneurs and the impacts on your life before taking the plunge.

Which brings me to some of the comments on this thread, which I want to highlight. First, Roger Darnell:

Personally, I’ve accomplished a lot entrepreneurially, 95+% of it with — and by virtue of — my wife’s encouragement. Surely, many businesses succeed where the entrepreneur is single and driven by his or her own ambitions, but it also seems to be that stable, supportive, nurturing relationships are a critical ingredient in success for a lot of us.

And then John McCaddell, on the extra freedom of starting your business earlier in your career and family path:

At the beginning seems like a wonderful time to start a new venture. That is what I did. There was no one else to support, nor payments to make, and guess what–people are willing to help because they know you are young! They know you have courage. I say, go for it!