PageOnce is a great app that lets you access all your online accounts from one portal, which is great if like me you're one of those people that pays most of your bills online. The list of supported services is quite exhaustive and includes everything from Amazon to Comcast to American Airlines. PageOnce also supports most email accounts and social networking sites like Facebook and Twitter. While I personally don't like using it to manage my email accounts, its great for managing utilities - I can look at my cable and phone bills from one convenient interface without having to navigate through Comcast and T-Mobile's awful account pages. Plus it also has an iPhone and BlackBerry app that let's you access all this information right from your cell phone.
Links: PageOnce