"Official BART ETAs in a simple, easy-to-parse XML feed: Build your killer app with the same real time data we use on the BART website, hot off the griddle from BART Central." - DeWitt Clinton from Bookmarklet

Best part: "Getting an API key: Psyche: you don't need one. We're opting for "open" without a lot of strings attached. So just follow our simple License Agreement, give our customers good information and don't hog resources. If that doesn't work for you, we can always manage usage with keys and and write more terms and conditions. But first we'll let our dev community know where to send the love letters." - DeWitt Clinton