If you are a WordPress.com user ever probably you know that they have a beautiful stats plugin for wordpress.com blogs. The plugin is released for self hosted wordpress blogs.
You need a wordpress.com API key to use this plugin, you can get that from wordpress.com by registering at wordpress.com. If you are using Akismet plugin then you already have the API key you can use the same API key for this plugin too.
Just Install the plugin from plugins administration, enter the API key and wait for few minutes to see your stats. It takes 20min to see your first stats and after that stats are updated for every 3mins.
Where do you see your stats:
You will see stats from your global dashboard at wordpress.com, that means wordpress.com servers will handle all your stats and you dont have to worry about your server load.
You can download the stats plugin from here.