Google Wave:  If you find a public wave about a topic of interest, and you want to continue to monitor new comments on that wave, you'll want to add yourself to that public wave, so in continues to display in your wave inbox.

This method works for me:

First search for public waves like this  http://activerain.com/blogsview/1285678/google-wave-find-public-waves   (The first few days, there was a managable number of public waves, now they are popping out on the list several per second)

Click on an interesting wave, and all the contents of the wave will display in the right panel.

Now look up at the top of the right panel, and click on the + sign to add participants.

The Add Participants dialog box will open.  If you don't already show up in the list, just go ahead and type in your own GoogleWave address.

As soon as your own little avatar shows up, DRAG it to the Participants Gallery at the top of the right cancel. (Clicking the plus sign does not seem to work when it is your own icon)

To confirm that you are added to the wave's participants, click the word "More" beside the participant gallery.

The participant gallery will expand to show everyon in the wave.

Some good basic info at Lifehacker:  http://lifehacker.com/5376138/google-wave-101