Useful for a band... perhaps less useful for anyone who can write software. If you can write software, then you'll make more money writing software than by doing just about anything else. (Cards on the table: I am automatically skeptical of anybody who suggests "Programmers should be like musicians" because I always hear the whispered insinuation "I should get their stuff like I get my music -- for free".)<p>I've got a minorly successful blog and people tell me I should go into writing. I think that's insane: do LOTS of marginal work, collect ~8% of the sales of the book from a pretty small number of people. Alternatively, do fairly little marginal work to promote my software, and collect 96% of each purchase price. Which is more than the cost of the book, to boot, because software doesn't have to get sold on some stupid hardcover/softcover basis and then rotated out of the bookstore after 5 months.<p>Software also scales to infinity if you can get the marketing/advertising done right, which is why I make far more from my sideline than from my day job on a per-hour basis despite doing much, much more impressive work at my day job by any technical measurement.<p>Similarly, 37signals has a lot of revenue streams. They've got several flavors of software, and several flavors of revenue which next to the software are pocket lint. I mean that in the nicest way possible -- Getting Real probably sold more dollars worth of dead tree than I'll make in the next decade, but in terms of impact on the bottom line, ONE small business buying their medium Basecamp plan for a year equals about SIX HUNDRED books. (PDFs make for a marginally better business -- then you only have to sell 30 copies.)<p>And you know how big of an audience they would need for advertising to compare with even ~1,000 app subscribers? Egads, it scarcely bears thinking about. (And they command premium rates for their advertising, via the Deck. Most people who think "Egads, I can't charge money -- I'll give it away for free and make it up on the volume!" are locking themselves into low-rate CPM and AdWords ads.)<p>The job board is a pretty sweet sideline, as far as things go, but unlike the apps it does not scale to infinity. After you get past N listings in a month, for N in the two digit region, your users start to hurt each other's experience of the product.<p>(The biggest reason for them to do so many things is to keep their name around so as to convince more people to use their web applications, which is where the lion's share of the money is.)