If the competition entry method is email or snail-mail, you could use a picture or photo with a caption as your answer. Ok, it’s a little more time-consuming, but if it catches the promoter’s eye they might just appreciate the time and effort you’ve put into your entry and pick it over the hundred-or-so written entries. Here are some examples of how you could use pictures:
“In 25 words or less, why would you like to win a car?”
“In 25 words or less, why would you like to win a holiday?”
“In 25 words or less, why would you like to win a computer?”
“My wife thinks it’s time for an upgrade”.
Note: Some email servers will block attachments such as pictures, so it might be better to use a picture entry as one of your entries in competitions that allow multiple entries. That way, if it doesn’t arrive, you still have a written entry in the draw.