Here’s how you can add the Fish Widget (and others)
This page lists the gadgets by abowman:
To add it onto your blog, find the web address of the gadget you want (Fish is: http://fishgadget.googlecode.com/svn/trunk/fish.swf)
Then go into your blog and Write a Post or Page. Use the “f” button in the WYSIWYG menu and paste the address (the file should end in .swf).
About 500 height by 500 width should be pretty good, but you can always change this afterward.