Totally agree with this one. There's nothing more annoying than someone telling you that a certain gig would be great exposure, as if they're granting you the privilege of working for them for free.
Writing is work. Not everyone can do it, and even fewer can do it well. Do yourself a favor; if you're good, don't write for free. Let these companies settle for a lesser crop of talent.
Steer way clear of free work, unless you're building your first 1 or 2 sites in your portfolio. You only need to prove that you can build something really good, and you could pretty much do a side project or two to do that. Your clients will want to dictate what the design looks like, so in many cases, you'll end up with a project that you're too ashamed to put on your own portfolio. Unfortunately, designers don't always get to do their job because the client thinks they can do it better with zero experience in the field. "What's this? White space!? That's absurd! I'm paying you, I can't have any of that nonsense!"
Working with the wealthier clients (ie startups who are funded) is a world more rewarding than the nickel and dime people who want everything and then want to negotiate for a lower bid. Wealthy clients are decisive and they let you do your job, so everyone wins--they get a good website, you get payment, and you can be proud to put the work on your portfolio.
We frequently will do a free smaller project for someone we term a "center of influence." So, if we deem that doing work for this person could lead to many more referrals and jobs in the future, we'll do a free project. Common example is putting an Ad Agency's website onto our CMS for free, so they can see our service and software, and then they will recommend us to clients in the future.
We've had great success and got into bed with some of our biggest clients this way. Also, there's probably a little guilt on their end that after we completed something for them for free that they "owe" us business in the future.
Although pro bono work has its place, this can easily turn into a trap. While you're giving it away (sometimes for good reason), you may be losing paying opportunities because you're too busy to notice them.
Using the phrase "pro bono" probably highlights the one time it is a good idea. If you're making lots of money (like a high-priced lawyer), then some well chosen philanthropic or interesting projects can be a good choice.
I've never freelanced before, but what I've heard is that it's a lot better to offer up a freebie than a low price, as long as (1) the freebie is small and fixed in scope, and it's mutually understood that any substantial support/follow-up work will be paid, and (2) there's a pre-existing relationship with the client, so that it can't be construed as a desperate/promiscuous willingness to do free projects for anyone.
The reason a low-priced project is bad is that it's difficult to raise to a decent price without upsetting the client. Whereas for a freebie, there's an expectation that the price can go up. Moreover, low asking prices tend to lead to low-end work.
Writing is work. Not everyone can do it, and even fewer can do it well. Do yourself a favor; if you're good, don't write for free. Let these companies settle for a lesser crop of talent.