http://www.activeup.com/products/components/activecalendar

From $149

Active Calendar is a server control that allows users to select a date and/or time quickly using a professional looking date picker with a client-side managed event system. No postback to the server required, no external script file required.

Active Calendar includes the Active DateTime technology. You can disable the visible calendar format and simply use the Active DateTime component of ActiveCalendar to provide a date/time selector group with client-side validation.

Active Calendar features - Client-side managed navigation. No postback to the server required. No external script file required. - Select month and year using selectors. - Select next/previous month and year using a customizable navigation system. - Includes time selection. - Choose between month names or month numbers. Fully customizable. - Utilizes the .Net component event model. - Culture independent. - Three levels of browser compatibility. - Fault tolerant. - Does not rely on any additional controls. - Better client-side navigation. - Ability to set an OnDayClick event on both client-side and server-side. - Better integration with VS.NET. - Styles can now be customized. - DatePicker mode using DHTML. - Extended client-side API. - Multiple dates and time span selection. - Ability to block selection on specified dates. - Ability to specify a custom style for a particular day. - Week number display. - Additional design customization using images. - Clickable footer that display and select the today date. - Full featured property builder with predefined styles. - Selected day changes with selection. - Day and month text fully customizable. - And a lot more !