I just got done integrating it into my forum and it seems to be working out very well. It's a lot like the Google spellchecker from the Google toolbar.
Check it out at my site as well if you like. Just make a new post to test.
I can. It's not more than a few lines of code on my side really. The server has to have the required aspell (to use pspell) as well as php installed and the pspell extension enabled in php.ini. If you have those, let me know and I can send you the code. I had to change the post window resizing to use css instead of columns and rows as it passes the size to the JavaScript functions for the spellcheck to manipulate the window while it is checking the text. That's really the extent of my modifications.