[TYPO3] Editing bits of Multiple tables on one form

[dave]

Hi
   I was wondering if there was an elegant way of editing fields from 
one table in the form based on another?

I am trying to make a semi-automatic keyword links system that works on 
content from a selection of arbitrary plugins. So I wanted to have a big 
table that kept all of the keywords and be able to extend all the 
plugins with an extra field which entered data into this table.

  I think it is possible to add a field to the TCA of the plugin, and 
then intercept the data before it throws a mysql error and enter it into 
the keyword table using a hook, oh and fill the data into the form with 
a hook before the form gets displayed but this feels somewhat hard work.

So basically is there a nicely designed way of doing this, and I am 
being blind in not seeing it?

    cheers
      Dave