...html/spec/codes.html

If you have a decent machine you can use all of these codes with the ALT sequence ALT-nnnn, where nnnn = the numeric code for the character with whatever leading zeroes are necessary to make it come out to four characters. You have to use the numbers on the keypad, not those on the top row.

Now, I allus thought that you needed a semicolon to close off the ampersand-nbsp sequence Pfranz suggested. Lemme try   three spaces and    four spaces. Hey, mebbe you can string them together and only need the semicolon to close off the string         nine spaces. Yeah, that's the ticket.