How do you guys handle it when a charitable organization needs to get some work done and asks that you do the work as a donation (i.e. free)? Do you refuse such requests, or do you handle it on a case-by-case basis, or what? I want to support my local community organizations, but after a while this starts to feel like those exploit-the-starving-artist posts like you see on Craigslist ("Need wedding invitation designed. No pay, but you'll get nice exposure and an item for your portfolio"). Thoughts?