Pail is a freelance version of Bucket, the #xkcd channel bot. This means that he will join whatever channel you want him to, as long as you message his owner, DarqWolff, and ask, while making sure the channel fits these requirements:
1) DarqWolff must become an auto-op, meaning the channel must be registered with ChanServ
2) You must make it a channel rule that Pail will not be stupided by the channel
3) The channel must be on Foonetic, but this will probably change in the future.
Note: Pail does not share Bucket's factoid database.