Jailbreak for More Features
Apple maintains obsessive control over the iPad, making it less like a computer and more like a media player. But you have an alternative: Jailbreak the iPad, and you can run third-party apps that weren't approved by Apple.
If you're willing to jailbreak your iPad (which means voiding your iPad warranty and taking full responsibility for anything that may go wrong), then you can also use the Camera Connection Kit to read USB sticks and SD card directories. (Without jailbreaking, you can already import SD-card videos and photos or attach a Compact Flash reader). With a bit more fiddling, you can read files from an external USB hard drive. Those are a lot of unnecessary hoops to jump through for such basic connectivity, but it is at least possible. Again, jailbreaking is best left for the tech-oriented or the adventurous.
You would connect the iPad to a computer, run Sprit and then be able to install apps through the Cydia interface. Cydia and iTunes apps coexist, so you can install apps like Backgrounder and Multiflow to enable multitasking (letting you listen to Pandora while working in other iTunes-purchased apps, say). Of course, multitasking is coming officially in OS 4.0. Notes: ProSwitcher (arguably the best jailbreak multitasking app for the iPhone) didn't appear to be optimized for the iPad (yet) at the time of writing. For jailbreak apps, sticking to those that have been reworked for the iPad will help avoid--though not guarantee against--unnecessary hassle.
Other jailbreak apps include iPad-ready versions of Wi-Fi Sync (wireless iTunes syncing), Winterboard (customized themes), and Dashboard (OS X-style widgets). You can also use your iPad with a mouse, run game console emulators and hand controllers, and otherwise do things Apple doesn't allow. Benefits will grow as the iPad jailbreaking community expands.
Access Your PC Remotely
You just left for the weekend but forgot to copy an important business file (or hilarious LOLcat) to your laptop. Use an iPad to retrieve the content. Several remote desktop-style tools present a live view of the distant computer, letting you control the PC as if you were sitting right there.
Whether you're reaching across the Internet, or just into the next room, the process isn't fast enough to play smooth video. So keep searching for that Hulu fix. But most other applications and slow-moving Flash games --such as Farmville--work if you can handle about 10 to 20 frames per second.
Among many choices, I like LogMeIn Ignition ($30 if you want to configure as little as possible) and iTeleport ($25), plus VNC Viewer ($10) if you want to manually set it up. You'll first configure the PC with a server utility (or an option built into the OS) first, then you can connect anywhere.
All three tools offer similar functionality. You'll zoom in and out with pinch gesture, and mouse around by touching the iPad. Two-fingered taps activate right-click, and other gestures help with the input. iTeleport includes more keyboard options, such as presets to control media applications, but I thought the implementation got in the way.
If you just want to sit back and control a computer hooked up to a TV, Mobile Mouse ($3) can turn your iPad into a wireless keyboard, multitouch mouse trackpad, and media remote.
Supercharge the Browser
Safari set a great standard for mobile browsing, but many alternatives reveal its missing features.
Starting with real tabs, Atomic Web ($1) adds many desktop-class benefits. Multitouch swipe gestures even toggle between open sites. But that's just the beginning. Atomic Web Browser can optionally omit images to save bandwidth, identify itself as various desktop browsers, let you customize the search engine, search for text within a page, modify its buttons, and more.
Safari will unfortunately remain as the iPad's default. However, you can create a bookmark that reloads a Safari page within Atomic Web Browser. In the Atomic Web Browser Settings menu, tap Install Bookmarklet. That'll open Safari and explain the process.