WordService by DEVONtechnologies is a great service-plugin which provides 37 functions to convert, format or speak selected text, to insert data and much more.

Since 10.6 (Snowleopard) services improved a lot (watch this to learn more). One improvment is that you can now select just the services you like.

So you can install “WordService” and than go to Preferences/Keyboard/Services and select the services you would like to use (e.g. Statistics).

You are now able to use them via the contextual menu in almost every application. (If you prefer you can also apply custom shortcuts to each service).

P.S.: If you are using LaunchBar you can also use all the services within the application even if they are unchecked in the System Preferences.

If you want to exclude services in LaunchBar go to the Index (⌥⌘I).