If you want to kill time then Yahoo games( https://games.yahoo.com) is a good site to visit. All that you need to do is register on Yahoo - this will give you access to not just Yahoo Games but to all the other Yahoo services as well, such as a free email a/c, Flickr, Greetings, Messenger etc. You will also need to download Java software if your browser does not have it already. The next step is to create what is known as a’public profile’. This involves choosing a username for yourself, which will be displayed instead of your email id., and the option of disclosing personal information such as age, gender, location, hobbies etc.
Once this is done you are ready to start playing. There are many games to choose from and they are listed under different categories like arcade games(e.g. pool), board games(e.g. literati, scrabble, checkers, mah jong), card games(e.g. spades, bridge, canasta), word games(e.g. word racer) etc. This makes it easier for you to choose the game that you wish to play. Apart from reading the How to Play page of your chosen game it is advisable to watch a couple of games in progress, provided that the players do not object, in order to familiarise yourself with the different features. This option of watching a game in progress is available in games like chess, literati, spades and pool(these are the only games which I have played so I do not know about the other games).
These games have some useful features such as:- 1. There is a colour-coded rating system which helps you in selecting a player of similar ability to play against. 2. You have the option of setting a time limit(except in Spades). 3. There are always hundreds of players present from all over the world at any time during the day or night(of course, some games are more popular than others). So you will always find someone to play against. 4. There is a text field through which you can chat with your opponent or partner.
All in all, it is a great place for driving away your boredom.