Slip a "mickey" = Mickey Finn?

[Jinx]

Two part q: Many movies and sit-coms used to use the phrase "slip someone a mickey". What is this, and does it refer to a Mickey Finn? And, even if not, what is a Mickey Finn, anyhow?

I know, this gives new meaning to "hidden mickies" (ala Disney) ;) !
- Jinx

[sewalk]

Cecil answered this one a long time ago here (http://www.straightdope.com/classics/a3_092.html).

[Annie-Xmas]

That article doesn't have my favorite Cecil line, which appeared in the first Straight Dope book (I'm paraphasing here): You might recall our discussion of 1890's Chicago saloon keeper Joe Hep on page XXX. 1890's Chicago salon keepers were obviously quite a crew.