Google Desktop is one of the best utilities for searching files stored in desktop. Since its inception Google Desktop has evolved from desktop search engine to a personal agent for displaying information from desktop and information from web like news, weather etc.
iGoogle is a customized start page like PageFlakes, NetVibes etc. and allows users to add news from their favorite websites and applications that collect information from internet. Google desktop allows running capabilities for iGoogle gadgets, however vice-versa was not true so far. The reason behind that was incompability between a web-application and software without the use of a plugin.
The new version of Google Desktop that is Google Desktop 5.5 (Windows-only, beta) enables users to add desktop gadgets to iGoogle page. Users can select gadgets from a directory, install a plug-in that establishes connection between desktop and browser and put gadgets for interaction with computer on iGoogle page.
A typical example is that of a music player which enables users to search music on computer and play it. There is another interesting system stats gadget which shows interesting statistics about RAM,CPU, battery usage.
I installed the new version of Google Desktop to see how this works out. Although, I was able to use gadgets from Google desktop on iGoogle, there was a display issue due to browser incompatibility.
Here is a screenshot showing iGoogle page with four desktop gadgets from googlesystemblog.