The GoBoingo! client is cool because not only can it automatically connect you to a Boingo hotspot (meaning you don't have to go to the login page and enter in some really long username and password), but it also gives you access to tons of Boingo-partnered hotspots that would be otherwise be inaccessible from Boingo.com.
For instance, if you are at the airport and you buy a Boingo Connect Day pass (which is $7.95 for US & Canadian access, $9.99 for international access) and then later that day, go to a McDonald's with Wi-Fi, you don't have to pay a separate fee at McDonald's, because they have a roaming agreement with Boingo. Boingo has a romaing agreement with AT&T as well, meaning that you can soon use your Boingo account at Starbucks.
The client is designed to be lightweight (the download is less than 1 MB) and it runs in the background, only popping up when it detects a Boingo network. After you have entered your account information once, you just have to click "connect" to login. I tested the client out at a few places in my neighborhood today, one that I knew was a Boingo-powered hotspot (because it always brings me to the Boingo login screen) and two that were Boingo roaming-partners and I was able to connect to all three easily and without any excess typing (or even better, money).
The GoBoingo! client is available now.