I've had a fair number of request for stuff beyond the usual t-shirts. I've thought about that before but the cost usually gets in the way. With unusual (well, compared to t-shirts) stuff like hats and scarves, not many people are likely to buy them and the per-unit cost would make them prohibitively expensive. If people want FES stuff, I try to do it as cheaply as possible while maintaining good quality. The t-shirts are a good middle-ground. I can sell those for $20 (including international air mail), provide a good-quality item that people enjoy and use the $1ish I make on each shirt to help offset the cost of hosting the site, etc. So everybody's happy, from what I can tell. I don't think I'd feel good about people paying like $40 for a FES-branded baseball cap or whatever.
I am looking into some printed items like posters, though. I've found a lot of great illustrations in some of the books we inherited recently. I may be able to scan them, clean the images up and do a small run of posters/prints based on that. Not just a big logo on a white background, but good-quality art prints of some of the amazing illustrations from the UZS era. I really love the style of those diagrams. And if I ever get my silk-screening setup working, that will open up lots of new possibilities like doing limited-edition shirts where I hand-screen 20 of them as part of the next Winter Charity Drive and then never print that design again. And the only way to get one is to donate $xx to whatever charity we're working with. But I'm probably getting ahead of myself
Designing and making stuff is a hobby of mine so I sometimes get carried away thinking about that sort of thing. I need to get caught up on a small backlog of membership packs before I start worrying about all of the little side-projects..