It is not possible to share videos from Youtube unless you use a gadget. Olaf Lederer from Finalwebsites has created a youtube gadget generator.
It simply works by go to the site http://www.finalwebsites.com/googlewave/. Find your youtube file link and the size of the video. The result is a bit.ly url like http://bit.ly/6S4gEW.
You can then insert this url into your Wave and you will get a gadget with the embedded video inside.

What I like about this gadget is that a new gadget is created pr user. The way this is done is by creating an url like http://www.finalwebsites.com/googlewave/gadget.php?url=3WYYu4pZt-M&height=344&width=452, which is converted into the bit.ly url. By using this url it is really easy to generate the gadget XML to embed the video.

I have previous tried to look at the Treeify robot by Peter Svedberg. But I never made it work, so I could make a demo of it. Now I have pulled together the time to have a look at it. This robot was suggested by David Cook from The Shiny Wave. If you have other suggestions of Wave applications, we should have a look please create a comment.

The robot is able to make a tree structure of your documents. The robot consists of a form where the user can administrate the structure. You can create new nodes, which corresponds to new Waves. It is possible to update the name of a node. This is a bit more complex to implement, but it seems to work just fine.

The robot is created in Java, but seems to contain links to a gadget. I have not been able to figure out how the gadget works. It looks like a quite complex infrastructure to make it work.

I have created a video showing how the gadget works.

This video show cases how it is possible to create links between different Wave. Using this architecture it would be possible to create some rather complex structures of Waves. It would make sense if you where using Wave to create a book or something like it.

HTML Gadget by Alex Tkachman lets you add HTML codes to wavelets. Its fairly easy to use. Anything from html tags, css to javascript functions are supported. For any webby like me who wants to spice up my wave a little, will  surely love this little gadget.

This gadget also allows the other participants to edit your code so this would be a nice tool for web developers. Although this gadget is very useful, it also has one big disadvantage. It’s a very unsafe plugin since it allows user generated  javascripts.  This gadget is prone to misuse from ill intentioned developers.

The Tic Tac Toe game by Sung Wu, is a gadget created in Adobe Flex. It is using the Wave-as-Client to create the interction between Javascript and Flex.

The game is not complete since a user can play both sides, which is not the idea of Tic Tac Toe. The game is more a demonetration on how it is possible to use Flex/Action script.

The gadget XML is hire.

The gadget is using Flex and demonstrate how easy it is to create gadgets in. I think it rather interesting to code the gadget in something other than Javascript, because it allows for different users to programme the gadgets. I think it is possible to make some gadgets look nicer in flex than you can in HTML/Javascript.

In wave you would often like to show some code to get some feed back on it. A gadget which can help with it is wave code prettifier by Milan Andrejevic . It is a gadget you can put into your Wave and you can then get formatted code in your wave.
The code gets highlighted as you type. The language is determinate automatically, or you can overwrite the control.

The gadget XML can be found hire.

You can enter you non formatted text on the top in the small window, and then the formatted text will be showed in the button panel. The buttum panel will be expanded as a result of data typed.

When you type something data is directly shared to the other users. If you type fast on a large text you are sometime send to the buttom of the field and complete the text at the end.

I would also like to see that gadget to have difference between edit mode and view mode. That way you would only see the formatted text as an ordinary user.

The gadget is written in Javascript and Jquery and uses a lot of standard libraries for code highlighting. The code in the gadget is only 29 lines. That is impressive.