Convenient javascript calendar (Date Picker)

Pure javascript (no extra http-requests on opening the calendar); tested in major browsers (IE(6/7), Opera(9), Firefox(2/3), Netscape); Windows-like look; can be customized with styles; convenient user interface; Incremental date/month/year change without opening the calendar; configurable first day of week; optional allowed years range; can be disabled; advanced scripting, onchange event is supported; the problem of overlapping Select's in IE6 is resolved.