I'll like to control my evince PDF viewer with a compact remote control with arrows on it that simply act like arrow keys on any Linux compatible wireless keyboard. Where can I get one of these.
One solution is if you have a mobile phone with bluetooth/wifi and touchscreen, then you can use that to control many Ubuntu applications, including Evince, LibreOffice Impress, Totem and Banshee. Many others are supported and you can add them yourself. It's a little bit complicated to configure, but doable. You'll need to install Anyremote on your PC and the Anyremote client on your phone. (It's a Java midlet).
There are also standalone numpads, which are very popular by accountants, but might also be of use to you. Google can help you find one if that's the sort of thing you want: http://www.google.com/search?client=ubuntu&channel=fs&q=usb+numpad&ie=utf-8&oe=utf-8