For example consider SELECT * statement that we use.
When ever we need to get the full record set of a table we are writing SELECT * FROM tblTable. So if we have 10 tables we need to write the same SELECT * FROM part 10 times or we may need to copy and paste that. Also mosstly, as developers we are using this statement for temporary purposes to just see what is there inside the table later we will delete the queries. In such cases the query shortcuts come in handy.
But to use them you have to set them up.
1. Open SQL Server Management Studio (SQL SMS) and go to Tools -> Options..., this will bring up the Options page.
2. In that, expand the Environment category and click on the Keyboard.
3. Now select a key combination which is easy for you to use (I selected Ctrl + 3.). Then in front of the key combination under Stored Procedure type SELECT * FROM and press ok.

Setup is done, now we'll use it.
4. Now open a new Query Window in SQL SMS. Then drag a table from the Object Explorer.
5. While the table name is selected, press the key combination (My case it is Ctrl + 3.).
See what happened?
It will run the SELECT * FROM tblTable query even though the query window is just having the table name.
Not only SELECT * FROM you can run what ever queries by using this method. But a limitation which I see is that we cannot create our own key combinations (I prefer assigning Ctrl + S or Ctrl + Space for SELECT * FROM rather than Ctrl + 3.).
I think this is useful to many developers to improve their productivity.