1) there once was a program i found that generated dictionary words by rearranging the user input characters.

• Generate all possible character combinations
• http://tartarus.org/~martin/PorterStemmer/ remove/correct words
• then inner join with a dictionary word table in your database to return valid names.
• filter words that might be offensive

then you can make different combinations given words, firstname, lastname
2) the md5 randomness should be last resort. you'll end up generating hard to remember usernames
3) also instead of using a hashing algorithm fixed length I would use an encryption algorithm non fixed length.. furthur reducing chances of duplicate based on user input

Leblanc Meneses
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