I am typing this on a 9-inch, 3G-equipped, almost-pocketable computer, running the best consumer OS money can currently buy. It costs around $400. Do you want one too? Here's how to get yours.
There are a lot of netbooks on which you can install and run OS X, but if you're mindful of the handy comparison chart those lads at Boing Boing Gadgets have compiled, you'll know that the Mini 9 is about as ideal a platform as you'll find for a Hackintosh ultraportable: Everything from wi-fi, sound and the function keys down to the optional integrated mobile broadband card and the SD card reader are supported and work as they should. No hardware compromises at all. It's awesome.
Generally, there are two ways to approach a Hackintosh install: Using a "slipstreamed" OS X installer image that's been modified to install on non-Apple hardware, or using a $129 factory-fresh retail OS X install disk in tandem with a special bootloader that does the necessary tweaking to let the install happen. The former can be easy enough, but it's pretty much illegal since it contains a pirated OS X install disk, and on top of that you'll run into all kinds of problems should you ever want to upgrade your OS or software via Software Update.
By using a retail OS X disk, you stay mostly out of pirate waters, and ensure that once everything's up and running, you'll be as close as is possible to having an actual Mac. Here we're doing that, using a method referred to as the "Type11" install, cooked up by a fellow of the same handle and his colleagues over on the MyDellMini forums, a fantastic resource.
Even though we're using a standard retail-purchased copy of OS X, the disclaimer: Apple does not like Hackintoshing. It violates the OS X EULA, and probably won't make the Dell folks too happy either, should you need to return your hacked Mini 9 for service. So, as always, proceed at your own risk.