1) Using perldoc://grep will generaly do close to the right thing (points to a perldoc.com search for foo). Also, using perlfunc:grep will link to the "the onsite docs are out of date, but..." page.

2) I'd personaly like the whatis:// scheme, and dict:// pointing to http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=$whatever. I generaly find m-w.com to give nicer results then dictionary.com, but either way. The important part is that dict:// is better then dictionary://.