Qwerty Warriors 2

Very much like Qwerty Wars but with all the annoyances removed! No longer do you have to press enter after each word, no more words obscuring other words and now all the words drop from the top allowing easy reading on the way down. When you start typing a word it appears in the status bar showing you how many of the letters you've hit so far. You get a multiplier increase each time you type a word without making a mistake, but obviously if you take too long then you start to lose health.
I'd advise against using the 'easy' level because it really is easy! Great help if you're learning to touch type.

Geoffrey's Quest

Geoffrey's Quest is a typical point and click escape game. Instead of escaping a room, you play Geoffrey who is searching an island for his kidnapped girlfriend Jen.

The game is ok but the ending is very creepy. Also, you can't see the items you pick up which is quite annoying.
 

FreeRice

This is quite a simple game: you are given a word and have to pick the correct definition, if you get it right you score 10, otherwise you score 0, repeat ad infinitum. However for each point you score the FreeRice people donate a grain of rice to third world countries.
The game tracks how verbose you are too and assigns you a different difficulty of word depending on your past ability. Each time you get three answers in a row right you go up a level, each time you get an answer wrong you go down a level (nb. this only kicks in after you've answered a few questions). My average level was about 29/30, and my maximum level reached was 37. The difficulty of each word is determined by how many people got it right and wrong, and so may change over time too.
The rice is paid for by the advertising on the site, and is donated to third world countries via the United Nations World Food Program.

IQ Test

So this blog has been going much longer than I imagined it would. This is post number 100! (That's an excited 100 as opposed to 100 factorial which is a lot bigger). To tie in with the one hundred theme here is a game where 100 is the average score - an IQ test. Admittedly it's an inaccurate measure, and favours more numerate people rather than more intelligent people.

The picture is from my first try, for which I scored 160/160, without understanding several of the questions. Good luck!