It's a great website, one of the few which I visit every day because of the extremely useful information they pull together. Take this post, for example:
Try the ComponentArt one. You'll have to pay a slight licensing fee, but its worth it. Wonderful set of controls, including:
- Treeview
- Text Editor
- Datepicker / Calendar
- "Snap" (movable DIV that can snap into any specified HTML element)
- Dialog
- NavBar (similar to Outlook's side bar)
- Extended Combobox
- Toolbar
- Splitter
- Multi-level Grid
etc...
All these controls are pretty lightweight (if you include a link to the script files and don't expect it to be generated on each page load) and perform lightning fast across all browsers. They're also quite extensible and have full documentation on the client-side and server-side APIs.