In the following poem, the first and last stanzas use only those letters found next to even digits (2, 4, 6, 8) on the telephone dial, while the middle two stanzas use only odd ones (3, 5, 7, 9). This method of dividing the alphabet puts about twice as many words into the first group (which gets the vowels AIOU) compared to the second (which gets only EY), while Q and Z cannot be used at all.
"Yes & No,"
Word Ways: Vol. 34
, Article 26.
Available at: http://digitalcommons.butler.edu/wordways/vol34/iss2/26