Kidz Club Stories, activities, skills practice and more. Many printable workbook-type activities. http://kizclub.com/index.html
Word Maker An interactive spelling/reading game. http://www.readwritethink.org/materials/wordmaker/
Online magnetic poetry You don't need a refridgerator for these magnet words. Move them around online to form phrases, sentences, poems. http://www.magneticpoetry.com/kidspoetry/playonline.cfm
Picture Dictionary Kids can look up lots of words. http://www.enchantedlearning.com/Dictionary.html