Nobelprize.org http://www.nobelprize.org/educational/all/ Nobelprize.org's educational section consists of 46 productions. Of these, 29 are interactive learning games of various sorts and degrees of difficulties. Most of them also includes a "Read more" about the subject.
Thiagi Games http://thiagi.net/archive/www/games.html - this site lists 300 ready to use games. The objective is for some of these games to be converted to e-learning. Many of these games can be built into online learning in breakouts or group activities using a forum or Wiki
Against All Odds http://www.gamesforchange.org/play/against-all-odds/ Against All Odds is about the global refugee experience from the time people are forced to leave their countries of origin to the beginning of their new life abroad. A series of short challenges illustrates the complexity and danger of the refugee experience. Thanks to Charlotte Wise for suggesting this game.
Tycoon Games https://www.learn4good.com/games/tycoonbusiness.htm Play free tycoon games online for children, teens, high school & college students on Learn4Good.com. Exercise your management skills and entrepreneurial qualities, and learn how to run a successful business or operation on these fun interactive business simulation / strategy games, RPG food service/ cafe/ diner games, farmer games, airport management games to play at school or at home on your computer. From simple fun to more challenging educational games & activities. Happy business management! Go Tycoon!
Simulation Games Check out this list of simulation games for a variety of fields and disciplines: https://en.wikipedia.org/wiki/List_of_simulation_video_games It is being added to regularly so it is worth checking back periodically to see if there is something you can use.
Hot Potatoes Game Creatorat: http://www.halfbakedsoftware.com/ The Hot Potatoes suite includes six applications, enabling you to create interactive multiple-choice, short-answer, jumbled-sentence, crossword, matching/ordering and gap-fill exercises for the World Wide Web. Hot Potatoes is not freeware, but it is free of charge for those working for publicly-funded non-profit-making educational institutions, who make their pages available on the web.
Quandary Simulation Creator at: http://www.halfbakedsoftware.com/ This tool was developed by the same folks who created Hot Potatoes. Described by its authors as a web-based action maze or interactive case study. Easy to use and a powerful tool for discovery learning.
Quest Garden at http://questgarden.com/- grow your own WebQuest with this very inexpensive discovery learning tool. See a copy of a webquest that I created for one of my courses: http://questgarden.com/16/46/6/090214092205/
Quizlet_ at https://quizlet.com/ Make your own flash cards to share.
GameBuilder https://www.wisc-online.com/gamebuilder - This is a segment of the Wisconsin Online Resource Site. It provides templates to create really unique games. In particular check out the "case study" game and the "media quiz" game. There is a small fee for long term use of the games.
Puzzlemaker at http://www.discoveryeducation.com/free-puzzlemaker - Free online resource for teachers to create word searches, crossword, math squares, mazes, letter tiles, cryptograms and other interesting activities to enhance lessons.
Online Learning Activities Collection at http://www.warrensburgr6.org/education/components/scrapbook/default.php?sectiondetailid=19832
Kubbu Game Creator at http://www.kubbu.com/
The Teachers Corner at: https://worksheets.theteacherscorner.net/make-your-own/crossword/