Netvibes has recently released a very cool update on their Widget API (see Ginger and UWA). It is now possible to create widgets that can be used in iGoogle, Apple Dashboard, Opera, Windows Live, Windows Vista, and of course Netvibes itself. I have just created two widgets for the two search engines Open Source Software and Java Developer Kit (JDK) Documentation which I believe are extremely convenient, but try for yourself!
For example, enter Word and click Linux to find open source alternatives for your favorite operating system. The widget remembers what your choice, and the next time you use the search you just have to enter the search term and press enter to search with the same operating system again.
Type concurrent and click 6.0 in the JDK search to find out about the concurrency package in JDK 1.6.0.
Are the widgets useful to you? Please tell me!