>>++>+<[
    [>>]+>>+[
        -[++++++[>+++++++>+<<-]>-.>[<------>-]++<<]
        <[>>[-]]>[>[-<<]+<[<+<]]+<<
    ]>>
]
"Random" bit generator using the Rule 30 automaton.
To get x bits you need 4x+4 cells.
Doesn't terminate; you will have to kill it.
Daniel B Cristofani (cristofdathevanetdotcom)
http://www.hevanet.com/cristofd/brainfuck/