Ok, thinking about Smart-Tags-done-right again… Here's a free idea. I'd like to see a Mac OS X service (probably need to be imeplemented in Java) that lets me download libraries of XLinks, then (optionally by using the service) tags words in my documents with a popup menu of possible links. This would build on work done in XLink, make use of existing Java-based XLink libraries, and be a total opt-in. Everything, of course, that Smart Tags aren't.