What about really small sized glass test tubes. They are often designed to withstand high heat (think high school chem class and bunsen burners). The only thing with them would be finding a way to keep them upright in the oven and upon serving.
Something I've tried is baking individual desserts in heat resistant china tea cups (it's soooo cute).
Hello chfcarolyn you shouldn't have to much of a problem with the shot glasses I have used them before for creme brulee on a degestation menu & they worked perfectly the only problem that I had was when I tried to caramelise the top with my blow tourch 1 ended up cracking so you may have to be careful there but other than that they should work fine just make sure you cook them in a water bath. & make sure your glasses aren't crystal.