If you have Pocket PC or Palm, chances are you've seen the Pocketop wireless foldable keyboard. At a very reasonable price you get a great product. If you use your PDA everyday to enter a lot of information, you will find it probably the best $79 bucks you spent for peripherals.
Or might turn out to be the useles device you ever bought... unless you are ready to cough some more dough. The reason - every piece of hardware is as good as the drivers you get with it. Otherwice it's just a scrap of plastic you can use to bang your head with.
In the case of Pocketop's keyboard you have to buy the drivers for additional $10 to $20. The price just jumped up with 12.5% to 25%. And if you change your device, you might as well face another 12.5% to 25% increase int he price.
I am sooo looking forward to the moment when my cable company will send me the cable box and small note that I could download the software for it for the small amount of $30...