Instead of setting up a store somewhere to list your ONE item, you put the template up on your website and link to it through gumroad.
Then, you give out the Gumroad link on Twitter: "Need a sweet Fireworks iPhone UI template? Buy it for a buck: gumroad.url"
Your twatting friends click it, give you a dollar, get redirected to your website. They download the template, you get a dollar - all in like 2 minutes while your oatmeal was cooking.