XBMC v13.1 "Gotham" has been released! See Gotham FAQ for details.
There is no manufacturer's name on this remote or the manual, but they appear to be from Ortek (http://www.ortek.com/html/pdt_view.asp?area=25&cat=154&sn=65). They are widely available on eBay. Maplin UK also sell an own-brand remote control (product code N18HC) that seems to be identical, and it is also sold as Hama 52451. The remote simulates the MS Media Center keypresses and will work out of the box on Windows, Linux and probably OSX. It also simulates a mouse, although it's no match for a proper mouse or trackpad.
Note that the the i button sends a right mouse click, which isn't much use in XBMC as the right click can't be mapped to an action. There is no way round this without using some helper app like Eventghost, but the Info action could be mapped to one of the other buttons.
If you want to add mappings for the four colored keys and the four keys below them here are the entries you need in keyboard.xml. The top left (Internet Explorer) key can't be trapped through keyboard.xml, but in appcommand.xml this button is <browser_home>.
<t mod="ctrl,shift">Notification(Key, Yellow, 3)</t> <!-- Yellow button --> <m mod="ctrl">Notification(Key, Blue, 3)</m> <!-- Blue button --> <i mod="ctrl">Notification(Key, Green, 3)</i> <!-- Green button --> <e mod="ctrl">Notification(Key, Red, 3)</e> <!-- Red button --> <o mod="ctrl">Notification(Key, u/Yellow, 3)</o> <!-- Button under Yellow --> <g mod="ctrl">Notification(Key, u/Blue, 3)</g> <!-- Button under Blue --> <t mod="ctrl">Notification(Key, u/Green, 3)</t> <!-- Button under Green --> <m mod="ctrl,shift">Notification(Key, u/Red, 3)</m> <!-- Button under Red -->
The * button sends a numpad-* keypress. XBMC v10.1 sees this as <eight>. XBMC v11.0 sees it as <numpadtimes>.
The # button sends a sequence of keypresses: numlock, alt, numpad-three, numpad-five, numlock. This generates a keypress with the ascii value 35 i.e. '#'. In v10.1 you can map this using <five mod="alt">.
For full Linux support see http://trac.xbmc.org/ticket/8827