If you looking for Mac apps, then you can check out All My Mac Apps, You can find Mac’s best progams and apps, the site include a search box, so you can search in a click for your Mac desktop gadgets, this site is nominated for site of the day. Go here to All My Mac Apps.

When Dashboard is activated, the user’s desktop is dimmed and widgets appear in the foreground. Like application windows, they can be moved around, rearranged, deleted, and recreated (so that more than one of the same Widget is open at the same time, possibly with different settings). New widgets can be opened, via an icon bar on the bottom of the layer, by dragging a widget icon out into the layer. After loading, the widget is ready for use.
Get more info and Apple dashboard widgets here