Online Teacher Grants

I have had great luck lately with an online teacher grant site: DonorsChoose.org. It's the easiest way to get supplies for projects or activities that I've ever used.
The site is specifically for teachers, and it has a very simple format. You follow a step-by-step "formula" to shop for materials (you order what you want on their site - through different vendors), explain why you need the materials, and submit. Then if (when!) you are funded, all you have to do is take pictures of your students using the materials, have the kids write "Thank You" cards, and send a packet back to donorschoose.
Teachers, let your imaginations soar! Last year I received supplies to teach my math enrichment classes how to bake (convection ovens, pans, measuring cups, and other gadgets), materials to open a school store (pens, pencils, sharpeners, notebooks), and books for the kids to read about the Periodic Table. This year I've received digital thermometers, Current Science subscriptions, fiction books with science content, reams of Astrobright copy paper, and toner for my classroom printer.
In the past when I've had a creative idea, I had to think of ways to get the materials for free or figure out how I could pay for it myself. Now, I just write a proposal and see if it gets funded!