Somewhere around Pd 0.47.0 and onwards Its been possible to send colour data using hexadecimal values for RGB to GUI objects. I found this very useful with dynamic object creation because the format is neater and more intuitive with a # symbol followed by 3x8bit hex values (eg #ff80ff pink).
Drawbacks, not compatible with Purr Data or Pd-Extended. The value is still converted to decimal in the pd file