Vista comes with a handful of fairly useless gadgets, such as an analog clock (um, there’s a digital clock on the taskbar) and an RSS feed that only shows two or three words from each headline. The good news: you can download more free gadgets from the Windows Live Gallery.
Here’s a filtered list of sidebar gadgets for you to browse. That link’s a little flakey, so if nothing comes up, try refreshing it a few times.
Well, the availability of gadgets is pretty bleak now, but here’s a few I like:

• Outlook info. Shows the number of unread messages in your inbox and upcoming appointments. Kudos to the author–he or she has really improved this from earlier versions. Right-click it and then click Options to select from different skins, including skins that don’t show tasks. If you have Outlook 2007, check out Outlook Upcoming Appointments, Outlook Tasks,
• Calculator. Not as useful as Calc (click Start, type Calc, and then press Enter), but it’s nice that it’s always there.
• Vista Calculator. Same thing, just a bit prettier. Note that you need to use the number pad on your keyboard or click the buttons with your mouse. The regular numbers won’t work (why?). If you pull it off the sidebar it adds a few features.
• Ping Gadget. It pings a host you specify and charts how long it took. Basically, this shows you in real-time whether your Internet connection is reliable–useful if you have a flakey Internet connection.

If you have a gadget you want to suggest, please do add a comment below.