/ will comment or uncomment highlighted blocks of code.
b will wrap a highlighted selection in braces.
Ctrl + 3 will wrap a selection into a region.
tc will generate a try/catch block.
mbs will write a MessageBox.Show(""); and drop the cursor in the quotes.
cws will do the same but with Console.Writeline.
m will create a method block (ms would do a method block that returns type string).
. will make a comment block.
