I can't pick just one. There are entirely too many to choose from.
One of my favorites is "The secrets of Raku Revealed" More for the eye candy.
http://lampworketc.com/forums/showthread.php?t=20601
My cheap easy "tip" is for arm rests. I bought 2 empty quart paint cans, covered them in fuzzy socks and they became my arm rests.