wp-forecast is a highly customizable plugin for wordpress, showing weather-data from accuweather.com and/or weatherbug.com.
wp-greet is a wordpress plugin to send greeting cards from your wordpress blog. it uses nextGenGallery to maintain your greetingcard pictures.
wp-monalisa is the plugin that smiles at you like monalisa does. place the smilies of your choice in posts, pages or comments.
wp-championship is a plugin for wordpress letting you play a guessing game of a tournament e.g. soccer