It's cool, and easy. Code structure heavily influenced by Kent Brewster's case-hardened javascript.
How-To
It's pretty simple. Here's the code needed to output Sunnyvale, CA weather. code can be replaced with a weather code or a zip code, unit can be replaced with "f" or "c" (Fahrenheit or Celsius)
<script src="http://playground.zpao.com/yweather/yweather.js">
{
"code": "usca1116",
"unit": "f"
}
</script>