The question http://emacs.stackexchange.com/q/2167/2609 discuss various spell checking solutions for Emacs.
Emacs ispell interface uses external tools such as `Aspell` or `Hunspell` for spell checking.
Considering the fact that many free dictionary files are available (for example by [Openoffice][1] see for example the dictionary file [en_US.zip][2])
I am wondering if it would be possible to write a native spell checking function in Emacs using such free dictionary files.

**Added**: More precisely I am wondering if there are existing packages which can be used for spell-checking (without using external tools such as `Aspell` or `Hunspell`) within Emacs. A tool which checks if a word is correct and if not suggests some corrections.

In case the answer is negative, any hint to do this would be helpful.

  [1]: http://archive.services.openoffice.org/pub/mirror/OpenOffice.org/contrib/dictionaries/
  [2]: http://archive.services.openoffice.org/pub/mirror/OpenOffice.org/contrib/dictionaries/en_US.zip