If your iPad (either version, 1 or 2) is currently on iOS 4.3.3, then yes, you can go to JailbreakMe 3.0 (via the Safari browser) and jailbreak it there with two easy button presses. No computer needed.
However, if your iPad is on any other iOS version, then no, you'll need a computer.
Please note iOS 4.3.3 on the iPad2 is the only iOS version that can be jailbroken.