We have restocked our Fantasy Naturale. This is a mercerized cotton yarn from Plymouth that is worsted weight. A nice quality yarn for a great price ($5 for 100g/140 yds).
Another perennial favorite is Sprout - this is the only bulky cotton I have found that is lightweight. It's also organic, incredibly soft, and comes in gorgeous colors. It's $10.50 for 100g/109 yds.
Firefly is a 75% rayon, 25% linen blend that is shiny, soft, and has a marvelous drape. We especially like it as a Slink. 50g/155 yds, $8.50.