Pogo
Online gaming site maintained by the gaming giant, Electronic Arts. Basically it offers casino style and some board games. There is a high availability of players and there are always other people to play with. The games are all based on Java applets and they are compatible with all browsers. A nice variety of games and quite a stable service. The free online games are ad supported. Additionally the site offers a great variety of downloadable games which are all original.
There are also free games available for mobile phones.

DownLoad Free Games
OWebsite with a few hundred trial version games to download. The games available varry alot in quality, from full fledged commercial titles to very basic arcade games that seem to be remnants of a few ages gone by.
Basically only the trial versions are free, but you can purchase (online) full versions of all games to download.

Arcade Town
Scores of flash based games that you can play for free on this site. The games are nicely made but are not very complex. They are reminescent of a games that existed in the ear of early home computers.
There are a couple of multiplayer games available also, such as checkers and backgammon where you can play against other human players.

Free Flash Games
A fair variety of flsh and shockwave based games are available to play on this site.
In essence the site is a directory of flash and shockwave games that are available on other sites and can be played for free.

MSN Gaming Zone
Microsoft's own gaming site. Many free online games available. The zone also supports the many commercial games that microsoft produces with multiplayer capabilites. There are many nice puzzle games available and there is also a section where you can play card games for real money. There are games that ca be played online and there are some others which need to be downloaded. Some of the games definetly appear on other sites as well (such as yahoo).
Requires the installation of additional active-x controls to work

Yahoo Games
Gaming section of the Yahoo portal. It offers a fair variety of games available for play via your browser. The card games are based on java technologies and most of the rest seem to be based on flash/shockwave.
The arcade games available seem to similar or the same to games available on other gaming sites as well (such msn gaming zone).

GameDep
Online repository of flash games, available to play for free. Games seem to be collected from various sources over the web.
The variety and quality are good and the site loads quite fast.
It doesnt look like the games are original but the selection is quite good.

Heavy Games
Online collection of flash games, with some pretty interesting content. Some of the games are really top quality. The arcade games available are some of the best we have seen in similar sites.
The only negative aspect of the site is that there are alot of advertisemnts and popus.
Still one of the nicest sites of the type out there.