As long as they're high quality, & nice t-shirts, I'd probably buy a few. Make them sort of reasonable though - like $15, or so? ^-^; And for posters, maybe $5-10? I know they're harder to ship... sweatdrop
And it'd be awesome if you got a donation letter for buying stuff. ^-^ I mean, if you spend that much money, it's got to be worth one!
And of course - Gaia-inspired items, like the hats would be very cool to be able to buy! lol I can't afford an OMG hat on Gaia, but I'd shell out $25+ for a real one!
And other merchandise... ;.; Don't go there. Sponser links are cool, but I don't think Neopets-like endorsements are the way for Gaia to go.