This site does not give you the codes for the symbols, rather it displays them for you to copy and paste. This is SO easy! You don't have to download anything, you don't have to type in special codes. All you have to do is copy and paste! Too cool! Click here to search for all sorts of symbols, including an airplane (my favorite).
To copy a symbol, highlight it and type CTRL and C at the same time or right click and select 'copy'. To paste, position your cursor where you want it to go and type CTRL and V at the same time or right click and select 'paste'.
Go forth and make your wall a prettier place! :)
Updated: Click here for more neat symbols! Thanks, Micael!
Check these out, too! Thanks, Calamityanne!