A comprehensive online distro creator? I have not heard anything about it.
There is MyDSL which is downloadable packages for Damn Small Linux http://en.wikipedia.org/wiki/Damn_Sm...e_MyDSL_System
Then there is Puppy Linux http://en.wikipedia.org/wiki/Puppy_Linux which allows you to "re-burn" additional settings & files to the same CDR
There is Slax http://slax.linux-live.org/ which allows the user to create a custom Slax CD _very very_ easily. Even in Windows! http://os.newsforge.com/article.pl?s...19246&from=rss

If you find it, let me know because I'm a distro nut!