I use a Fluid app to engage with Google Wave. The TC Wave has links to how to do this but the TC Wave is becoming harder and harder to navigate and find things. So here's the blog post with links to how to integrate Fluid and Wave and Growl.
Download Fluid then drop by??Guillermo Rauch's devthought blog for how to create the app (plus a link to a very nice Wave icon to use for your Fluid app). Then if you're interested in Growl notifications when new messages arrive at your waves, install Growl and then add this script to your Fluid app. (Guillermo's page describes how to install a script in a Fluid app.) Growl notifications only work when your Fluid Wave app is open.??
I'm happy with the Fluid Wave app performance and I've had no serious problems. It can be slow but no slower than Firefox (3.0.15). I have heard Chrome is snappier but I don't think Google has released an official Mac OS X Chrome yet.
Please add any useful links about Fluid, Growl, Wave etc.