Has anyone ever considered how easy it is to include syndicated Google Gadgets in a Joomla! site using the Custom HTML module (mod_custom)? This page lists all openly syndicated Gadgets:
Just find a Gadget and select "Add to your webpage". Then set any parameters and click "Get the code". Copy and paste the code into the source of a Custom HTML module and you have a Google Gadget on your site!
By the way, remember to turn off any code cleanup options you may have on in your Editor or the <SCRIPT> tags will get stripped out when you save.
Of course, except for width and height, you don't have much control over the look of most Gadgets. But this easily can be corrected by viewing the code on a particular Gadget's "about" page, tweaking it, and submitting it as a new syndicated Gadget that looks the way you want.
So, if you can't find the Joomla! module you're looking for, you might consider looking for a Google Gadget that does what you want instead.