HTML5 Input Type Date will allows the user to select a date.
To make you life easier you can now call this date picker by simply using this
type="date" on your input field.
May be looks like this way :
[php]<input type="date" name="birthday" />[/php]
Currently the latest version of Chrome, Opera and Safari browser supporting this.
If you are using any of this above browser then you are lucky to see it on action
The code i used abode is:
Date Picker: <input type="date" name="bday" />
<input type="submit" />
Or it may look like the screenshot below