I've never been big into MDMA, but I've sampled a number of pills (and equally as much molly) over the years. Here's what I can remember:
White Sunflowers- the famous MDA ones
Yellow, Lime Green, and Aqua Motorolas- pretty good
White Euros- good clean dose of MDMA
Pink Yin Yangs- decent
Green and Blue Rabbits- weak
Blue Dolphins (many times)- varied
White 007s- Really good (around 2002)
Blanks from Cali that were domed on both sides- BOMB shit
Light Blue @ signs (called emails)- good
Red Anchors (circa 2000 or early 2001)- BEST PILL EVER IMHO, though that was during my first few times w/ MDMA so maybe I'm biased
Those are the ones that really stand out, I've probably seen hundreds, just didn't consume most of them. These days if I want to roll I go w/ crystals/powder, as the stuff around here is pretty good.