Lace is a free web communications experiment written in PHP, Javascript, XHTML and CSS. Lace takes advantage of XMLHttpRequest if it is present, and degrades gracefully if it is not.
My article Lace 0.2 Expectations explains more about where development on Lace is headed.
Features
Lace 0.1.3 - 10 Oct, 2005
Be sure to read the Requirements, Support and Todo sections first.