Challenge by: reminiscent-afterthought
I don't know if you guys are familiar with the game (or maybe you know it called something else), but Alpha and Omega is where the following word begins with the last letter of the previous word. For example, if the first word is apple, anything starting with the letter "e" can follow it.
As far as the challenge goes, you pick a starting letter and I'll give you another one. Then you pick a word that fits into that; the second letter can be anywhere in the word (except the first letter naturally), and that becomes your prompt. Write a poem, post the link here, and the start of your next word becomes the last letter of your previous one. I give you a new second letter, and away you go.
Make sense? No; maybe my dot-points eg. will help.
There's really no limit, unless you run into a corner where you can't think of any new words. :) And, naturally, there's a limit to the sort of words you can pick. Stick to one language and unhyphenated words and go wild otherwise.