Modification (from scn9a's original) made was to add the date (yy-mm-dd) to the time (hh:mm:ss) to create a truly unique RGB color in hex format for the current date & time. i used the following math of yy+hh=rr, etc and then background-color:#rrggbb.

Links to my variations (and the original I based my varitions on):

  1. This page
  2. Date (DD-MM-YY) & Time (hh:mm:ss) combined
  3. Date (DD-MM-YY) & Time (hh:mm:ss) combined & expanded to full color range (#000000-#FFFFFF)
  4. Time only in true hex value, each part is converted from decimal to hex rather than using the decimal value as a hex pair (as is done in the original provided by Update 2017-12-12: The site appears to be defunct now.
  5. Time and date in milliseconds since Jan 1, 1970 with true decimal to hex conversion constrained to the range of #000000-#FFFFFF using the modulus (%) operand. Date and time shown in standard formats