Jailbreakers have already cracked iOS 5's Notification Center widgets, according to 9to5Mac. Notification screen widgets are little apps -- or widgets -- that run in the new Notifications Center in iOS 5. iOS 5 will ship with two widgets, stocks and weather. However, as usual, the jailbreak community wants to push things forward faster than Apple does, and they've already come out with a host of third-party widgets.
MacStories has an excellent roundup of some of those custom Notification Center widgets but, as always, if you want to use them you'll need to jailbreak your iPhone. One of my favorites is SpringPrefs (shown at right), which shows you details about your iOS system information, including the amount of free RAM, your Wi-Fi and Data IP addresses, and your firmware number.