[Update 10/23/09: Version 3 of the widget is here.]
[Update 9/3/09: A new version of the widget is here.]
I've been messing around with this stuff for a few weeks now, but tonight I had a real itch I wanted to scratch so I banged out a small search widget which is actually pretty functional. I call it "Q Search" (Q for Quick), and it's simply a search-page launcher - but one that's optimized for the least number of clicks from the home page of the phone.
You can download it here: qsearch.wgz.
The impetus for the widget is amount of time it usually takes to call up a search page and get results, even if you use a search app or a bookmark - then to close everything down again and get back to the home page is a pain as well. I wanted something that used as few user-actions as possible to get in and out of a site.
I should mention that mobile widgets are fun and easy if you're a developer, actually. It's insanely simple to whip something together with no special tools - like normal web dev. The .wgz file above is just a zip file of the index.html, style sheet, images, etc., so nothing proprietary, and you can even include Flash Lite in the package as well. You can find the details on how to develop them in Forum Nokia's Library. Also I recently discovered that Vodafone is using Opera's widget runner (which is mostly compatible with Nokia's) and that all of this is being guided by a W3C Widget spec. (It's like I've been asleep for two years, and all this stuff just popped out of nowhere!)
Now whether mobile widgets will ever take off like native apps? I tend to think not because of the generally lower-quality user experience combined with the hassle of having to "install" and manage the apps, but if you want to hack at your phone, it's a quick and simple way to do it.
P.S. Wow, that was the first real blog post I've written in months!