It was only a matter of time before people started writing their own applications based around Google Wave and the first one that's come to my attention is Waveboard. Waveboard is an application for Mac OS X (and soon the iPhone as well) that puts your Google Wave account into an application.
What I don't yet understand is the point of it - anyone who has Fluid installed can just create their own Google Wave application using that which makes some dedicated software seem overkill. Even the iPhone application is no different really to just opening it in Safari on your mobile (since you can create a homepage button to it too). Maybe eventually they'll add a feature or something that will make these applications worthwhile, but until then I'm a little sceptical.
A more useful tool I've been using is the Wave notifier extension for Firefox. All this tool does is periodically check to see if there are updates to any of your Waves and will display a count of the number of Waves with updates. On hovering over the indicator it will then list each updated Wave with a timestamp of when it was last modified.
