well, the renaming prog I always recommend is called simply
Renamer
freeware, and i just verified that in the 'edit' menu, under 'misc' is 'insert random number' - which then pops up a dialog that gives you a few options...
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- + - ° GiRLie GeeK ° - + - °
01110010011011110110111101110100001000000110110101100101
Therell be days/When Ill stray/I may appear to be/Constantly out of reach/I give in to sin/Because I like to practise what I preach