Here is a website listing lots of low-tech (no computer needed) ideas for practicing spelling words. There are also some websites listed where you can do creative things with your words like create mp3s from them and listen to them, animate them and more. I haven't checked out all the links, so proceed with caution. Wordle is pretty neat!
Lastly, if you are looking for something very simple, Scholastic has a Spelling Wizard that allows you to enter 10 words, then creates either an unscramble puzzle or a wordsearch.