To get access to Gmail, Reader, YouTube and many other Google services in one click, you can check out the Terminal for Google extension, as mentioned before.
The following will show you another similar Chrome extension — Black Menu, which is also available for you to access all your prefered google services, but more interesting with 3 special features:
1. You can search
You can search Google+, Gmail, Maps and some other Google services, while some results (such as Maps and YouTube) will be displayed on the extension window, the others (such as Google+, News, Gmail, etc.) will be displayed on the search result pages of the service you choose.
2. You can use some services directly
While Terminal for Google is only available for you to click on a service's link and visit its homepage, Black Menu is also available for you to watch YouTube videos, to read Google News, to view your Calendar events, and even to translate inside its extension window.
3. You can visit different tabs of a service
Instead to click the service name (such as Gmail) to its homepage, you can also click on a tab name (such as Contacts) and visit the tab (such as Gmail Contacts) directly.
Besides the above 3 features, Black Menu is also available for you to add tasks, to filter YouTube videos, to view Drive files, and even to do something else.
Although Black Menu is much interesting than Terminal for Google, which will display the notifications of Gmail, Google Reader and Google+.