As the first part of my Google Wave developer sandbox review handled basic usage, this article will be about some more advanced features currently in the Google Wave developer sandbox.

Attachments

Adding attachments to a wave works similar to adding attachments to an email. You click the attachment button, select one or more files, click submit and voila. Your files are uploaded to and displayed inside the wave.

You can attach almost any filetype to a wave. In case you have one or more image files the thumbnails of these files are displayed inside the wave. When you click on a thumbnail the larger image is displayed on a dark background. When there are multiple images added to a wave you can browse them by clicking the image button at the bottom and selecting “view as slideshow”.

The last blog post, Understanding Google Wave, discussed the architecture and technical underpinnings of Google Wave. In this post, we will look at different ways of developing with Google Wave.

There are three ways you can extend or use Google Wave in your applications.
Embedding Wave
You can embed a Wave into a web page by adding some simple JavaScript code.
The Wave Embed API provides the WavePanel object which can hold a wave. You ask the WavePanel to use an HTML element on your web page to show a wave. The conversations on the wave will be visible in the WaveClient.
The steps to embed a wave on a web page are -

Continued from part 3: extensibility.
Google Wave in many respects is the ultimate collaboration tool. It can be best compared to Wikipedia but instead of striving for encyclopedic accuracy people can work together to strive for their own outcomes. In doing so they can add all kinds of content, including gadgets and robots that can give a helping hand.

Continued from part 2: unified messaging.
Google Wave provides two ways to add new features to Wave: robots and gadgets.
A robot resides on a Wave provider and receives all updates for those waves it participates in. Robots can also update wave content, for example by automatically replacing www.google.com with http://www.google.com. Other examples of robots in the demo video is the spell checker and the translation feature.
A gadget resides on the Wave client (in the browser) and changes the look and feel of the wave. A Sudoku game could for example be a gadget.
Robots are ideal for heavy computations, and when access to external data is required – like a CRM database or a web service – which cannot be accessed by a browser.