eQuizShow is a website for creating Jeopardy-like games.I really like the simple interface and the lack of clutter on the screen. It is free, but you may donate money if you'd like. It can be used with or without an interactive white board or on an iPad, so it could be used for small group or individual practice as well. If played as a large group, you are able to select the number of teams and it will keep score for you--a big plus!
After you make your game, you are given a link to your game (See one of mine here.), and you are able to go back and edit your own games and search for (but not edit) others' games.
One word of advice: when you create a game, give it a specific name to help you and others in the future. "Science Vocab" is not as good as "Cell Biology Vocab". I started using the name of my textbook and the chapter for the title.
There are lots of game websites and apps but I have had good luck with eQuizShow. It is easy to set up and easy to use.