The old school method to let user select date and time are using drop down lists (day, month and year). Now, we can use a calendar, timepicker to replace the old way. Since it's picked from calendar, it decreases the chances of invalid date. I like them.
Sometimes, we get really annoyed when we have to type in message in such a small space (a textarea), and we have to scroll up and down, left and right (sometimes) to read the entire message. Say no more to scrolling! Add this autogrow/resizer capability to textarea to avoid that.