to prototype or not to prototype, that is the question

It looked as a simple task: make a simple html prototype for a potential client. It then ended up like a horrible nightmare of html delicatessen: ooooh we must convert this png into gif because it would be smaller... why don't we make the border of the tables fancier? ... oh let's put px instead of % ... no... better put % instead of px, and no pt ... and by the way let the tables use the 100% of screen width (even if I repeated once and once that reading small 10 px text along a 21'' screen is like a harakiri).

Finally it ended like it started, gracefully, as a simple prototype. Remember: don't even let the prototypes get into final applications (specially when the deadline is very very close); don't go into unnecessary details and focus only in the really important things...