I just stumbled about an link to a disambig page and thought "there should be a tool to fix this here and now". I haven't heard of one before, so I wrote one.
Full description: http://en.wikipedia.org/wiki/User_talk:Magnus_Manske/fixdisambig.js
Basically, when you follow a link and end on a disambig page, select the text of the link it /should/ have linked to, and click on a sidebar link (or click on the sidebar link and enter link text manually).
The script will edit the page /you just came from/, replace the link(s), and show you the diff. Click "save page", and you're done!
Cheers, Magnus