(ed: not sure if this selection actually counts as 'rhyme' or if it should be in the 'games' dictionary, or just in the general 'slang' one. Anyway - here is is... for now!)

Basically 'dipping' was a selection process determining who was/wasn't 'it', prior to a game of tug/tag/whatever. Participants would put their feet or hands in a circle and someone would point in turn whilst reciting a short rhyme, moving round the circle with each word, or syllable, depending on the rhyme or, often, the dipper's fancy. eg.:

Ip-dip cow shit
Hanging on the line wind blew
Shit flew
Out pops...
You."

In this case, the owner of the 14th foot pointed to would be removed from the circle and the process repeated until only one was left and they were 'it' (nb: 'on the' counted for only one move, for some reason)

An alternative ending was:

"..out pops...
Y.O.U.
are
it!"

(ed: though this was often to force the selection of a favoured individual!)

There were numerous rhymes and variations, which would inevitably result in disagreements, especially in the case of the latter version of the above rhyme.

When "dipping" in school in Merthyr Tydfil in 1960's South Wales, this contributors version, and my own following, are both embarrasingly racist. But in defence, it was what we grew up with and knew no better:

Enni minni minny mo
Catch a nigger by his toe
If he screams pull his tail
Send him off to Cardiff jail,

Eenny meeney miney mo
Catch a nigger by his toe
If he wriggles let him go.
Eeny, meeny, miney, mo.

(ed: Other such rhymes include the eternal "one potato, two potatoes, three potatoes, four... " sequence. If anyone can send in a version I'd appreciate it)

(ed: As an unrelated side issue I've been given to understand that the words 'Eenni meeney miney mo' (whatever the spelling), are actually the numbers '1 - 4' of an archaic forgotten numbering system. Occasionally I make enquiries to se if the linguistic root has been established but so far with no success. If anyone has information to pass on regarding the issue I'd appreciate it.