Create customized wordlist

Create a wordlist containing words from length 1 to 6 with characters 0-9 and A-F:

crunch 1 6 0123456789ABCDEF -o crunch1.txt

Create a wordlist containing words with length of 4 with characters mixed alpha-numerical

crunch 4 4 -f /usr/share/crunch/charset.lst mixalpha

Say you want to create a wordlist with a length of 8, with the following characteristics:
[Capital Letter] [2 x lower case letters] [2 x special chars] [3 x numeric]

crunch 8 8 -t ,@@^^%%%

NOTE: This command will output a file of 160 GB, with over 19 billion entries!

@ = Lower case alpha characters
, = Upper case alpha characters
% = Numeric characters
^ = Special characters including space