A House Rule

A magic-user gets a +1 to all rolls associated with the resolution of a spell, provided the player introduces the spell with a short, improvised, rhyming incantation.

The rhyme need not be especially clever. However, the spell backfires horribly if the player reuses a rhyme, or rhymes a word with itself.

At the DM's discretion, the bonus may be increased to +2 if the rhyme leaves the whole table cackling.